Their relationship's not perfect - far from it, actually.
It's always the little things.
They're not like Finn and Rachel who have messy break-ups that affect the mood of all the members of New Directions because everyone feels like they have to pick a side or die in the crossfire. They're also not Quinn and Sam, Artie and Brittany, Puck and Lauren, or Santana and… whoever she’s ‘dating’ that week.
Their fights are considerably less dramatic: no baby drama (thank god), no making-out their significant other's best friends or traumatic eggings in the parking lot; nothing that crazy.
Instead, it's always the small, stupid things that instigate disagreements and bickering. Things, according to everyone else, shouldn't matter - except they actually do, at least they matter to Mike and Tina.
Mike doesn't think he'll ever understand Tina's dislike of dim sum; it's his family favorite.
Before moving to Lima in middle school, he grew up in the Bay area where his Asian friends always outnumbered his white friends. He's the son of second-generation Chinese-American parents- both who are quite proud of their cultural heritage and want to make sure that he feels just as strongly.
Mike remembers spending the occasional summer or winter vacation in Hong Kong – visiting relatives whose exact kinship still remains a mystery to him.
Every time they have dim sum, it brings back memories of Sunday brunch in Chinatown or the packed, noisy teahouses in Kennedy Town where Cantonese is spoken – or more accurately, yelled – in order to be heard above the organized chaos. He knows all the names of his favorite dishes: har gau, char siu bao, ngau yuk and haa coeng and they taste like home. While the Lee’s Chinese restaurant in Lima isn’t nearly as good - it’s passable enough, and his family has been going there for years.
Tina doesn’t understand - and she doesn’t think she ever will - why Mike always insists on having dim sum (with his mom) whenever they go out. Dim sum’s fine in moderation; but there aren’t a lot of vegetarian options on the menu so she’s usually stuck with just egg custard buns and taro cakes.
She likes variety; she likes Breadstix for their salad options as well as their soups and portobello pastas. It wouldn’t hurt if they changed things up a little bit. As much as she likes Mrs. Chang, Tina also wouldn’t mind an unchaperoned date with her boyfriend every now and then.
There are other things, too.
Tina knows that she’s prone to jumping into all sorts of crazy conclusions (Sectionals, anyone?). Mike tactfully pointed out after the incident that she has nothing to worry about – that he and Brittany have never been anything more than friends, and more importantly she’s not his type (“She’s not you,” Mike had said, grinning at her). But it doesn’t change the fact that she can get bit a jealous and okay, maybe more than a little insecure about their relationship.
Tina knows she’s a decent dancer, but she’s got nothing on Brittany, who moves as though she had been born to dance. Brittany might be not be the smartest girl in their class, but she’s an amazing dancer. There’s no one else in glee or the school who can match her, except Mike.
It’s hard not to feel worried when the two of them are so comfortable around each other that they communicate non-verbally when choreographing dance numbers for New Directions. Harder, still, when she knows that Brittany’s blonde, popular, gorgeous, and a cheerleader. Half the football lusts after her like a cliché from a teen movie.
Brittany is everything Tina’s not.
It’s not that she doesn’t trust Mike; she does, but she doesn’t understand how he can like her when she’s a social pariah and he’s a jock. She feels – inadequate, like it’s not supposed to be this easy, which is why their fights are always over the same things. She knows she should stop acting insecure, but it’s not like there’s a button she can push to turn it off so she can stop feeling like the melodramatic one in the relationship.
It actually goes both ways.
In hindsight, Mike figures that the thing with Beiste had been stupid (his own fault – he had been the one who told Tina in the first place), but in the heat of the moment – he didn’t think.
The thing is, that he constantly worries that he likes Tina more than she likes him, because he had been crushing on her before she broke up with Artie.
It’s a tough feeling to shake off; especially when it turns out that Tina’s the more experienced one in their relationship (and her first boyfriend had been Artie). Things might be strained and weird between the two of them, even though Artie’s dating Brittany now, but Mike knows he didn’t imagined the look of awe on Tina’s face in the choir room when they saw Artie with his ReWalk.
It’s a persistent, nagging worry in the back of his mind.
Mike doesn’t think he’s half the martyr that Tina sometimes paints him out to be.
To tell the truth, he actually finds that a little annoying, because it’s like she’s convinced that he’s something he’s not.
He’s not an asshole football jock who lock guys like Artie into porta-potties (because that’s just cruel, disgusting behavior) but he’s also not an admirable, stand-up guy like Finn who would stand up to Karofsky or Azimo. Instead, he slinks into the background and tries his best not to be noticed at McKinley (glee club sort of derails his plans) or accidentally become Karofsky’s newest target.
Being a coward isn’t something he’s proud of: it takes careful prodding from his girlfriend for him to do something he should have done ages ago, stand up to Karofsky and call him out. He’s not being brave, saying all those words in the locker room – when it had actually been Sam who really physically made Karofsky listen. His words had been meaningless.
So the first time he gets slushied, it’s a nasty shock to his system, literally and figuratively. But it had been something he'd been anticipating since he first joined glee last November.
Tina’s vocal concerns that their relationship affecting his social standing at school has little to do with the slushie facial. When it comes down to it, it’s more like Karofsky holds grudges like no one else because he’s a douche with anger management issues, so it’s frustrating to try to convince her that it’s not her fault that he now knows exactly which shirts in his closet are machine-washable and which he can only wear on weekends, when he doesn’t have to worry about them getting stained with corn syrup.
It’s the little things like that – and stuff like performing solos and duets in front of everyone in glee – that cause them to have minor disagreements. Some of them get resolved over time or compromises are made.
(After “Sing!” Tina’s delighted when Mike agrees to sing a couple lines of “Marry You” during Finn’s mom and Kurt’s dad’s wedding.
Tina agrees to dim sum every Saturday with his mom, as long as they go to Ruby Tuesday or Breadstix when it’s her turn to pick.)
Other issues aren’t glossed over.
Mike knows that Tina’s aware of her flaws and is working on them and he’s been trying to do the same. Tina knows that Mike honestly has no regrets being her boyfriend, even if it means he has to keep an extra t-shirt in his locker during the week.
Their relationship can be shaky at times.
They know that it's public knowledge that they officially got together before Tina and Artie broke up (even if Tina had considered them broken up long before she dropped the bombshell on her ex-boyfriend). Compared to the other relationships in the club, they know that theirs is probably the most normal and boring (although the term 'normal' is probably subjective) since they're not the type to sing about their feelings in front of their friends. But that doesn't mean they don't have their own problems.
They hate all the implications from others that they’re only dating each other because they’re the only two Asians in their year. They’re both offended and pissed off when Jacob Ben Israel makes a post on his blog that suggests the two of them are actually somehow related.
(The two of them corner him in the hall the day after and make it very clear that Tina’s family is Korean, Mike’s family is Chinese, and if he doesn’t delete that post, they will see exactly how lenient Figgins is with punishments when he thinks he’s dealing with the daughter of an Asian vampire.
Tina says this all in a charming voice, smiling pleasantly at Jacob while Mike stands by her as moral support and laughs in sincere admiration.)
Their relationship isn't perfect, but it works, and that's enough.