Marrying a cheater?

I’ve been feeling down lately. I’m a mother of two and their dad and i have been broken up for a year. I left him because he didn’t want to marry me he kept saying in 2 years then it changed to 3. Plus he was cheating repeatedly but because I wanted to do right by christianity i was willing to stay but it just got to be too much. I’m not fornicating anymore but i just feel so bad about myself. Should I try to work it out with my kids dad? I feel so much judgement being a mom who was never married.