He cheated, but I just won’t leave.

I need help. When I finished high school I moved half way across the country on my own because I had no plans of a future. I met my fiancé while I was out there and fell head over heels in love. We loved each other so deeply and became each other’s everything. After a year of living together, I got pregnant. We moved back to my hometown so my family could help support us. Through the next 3 years we moved into our own place and had a second daughter. Now I found out that for the last 3 months he has been texting, hanging out with, and kissing a girl he works with. At first, of course I blew up at him, packed mine and and kids things and left to my moms. But I just couldn’t stop. I wanted to know when, how, and why it happened. So I went back, and I begged for him to choose me over her. We went on like this for a whole week. Then I went and saw a therapist, who really opened my eyes and helped me find a way to talk to him. So we did. We talked, he came clean about everything to me. I found out the reason he had justified in his head that this was okay, was because I hadn’t been treating him right. And he’s not wrong, I was neglecting him a lot. I focused so hard on proving I was a good mother I forgot to be a good partner. And I can accept that he has needs that I wasn’t filling. He has had A LOT of trauma in his life, more than anyone could believe. And was never taught to express that. I know I sound like I’m making excuses for him, but it’s always been a huge factor in our relationship. I want to start this over, I want to be better people and really learn how to love each other the right way. We were so young and then had children and never got to do the things we wanted to do. Now I am ready to move back by his family and start the life we always dreamed of, but he just can’t let her go. He finally told her the truth about me because he had been lying to her saying that we were only co-parenting. Now she has blocked him and he is really upset (again, I can understand that). But he just won’t choose, every time we talk he changes his mind about what he wants. One moment he has never felt this much love for me, and the next he doesn’t want to fight anymore. But we have 2 young children, we connect so well, and we have been though so much. I know I should probably just leave. But I’m only 21, I don’t have a single friend, my family doesn’t help because they all work full time, and I haven’t had a job in 5 years. I feel like i’m stuck and I have no way out. I want our family, but I don’t want to be the only one working for it.