There are two parts to Natasha’s life: Before Clint and After Clint.
Before Clint is when the Red Room owned her, and her employers didn’t give her the option of saying no. It’s a time of violence, both towards herself and others. She broke free of the Red Room when she burned the hospital to the ground, but the chance to change her ways never came.
After Clint is simpler. Sweeter, almost. She still chooses her missions but backup is available to her, unlike before. She enjoys her missions with SHIELD and Clint.
She’s slowly wiping red from her ledger.