Infidelity and dependency

I’ve been with my partner 12 years we have 4 kids together. My partner has cheated on me multiple times during our relationship. He’s made it so I’m financially dependent on him. I feel like I have to stay in the relationship for our children, but being with him makes me feel horrible about myself. I don’t have a supportive family to help if I left the relationship. Feel completely trapped and like I’ve given the best years of my life to someone that has never really loved me.