How did you accept the fact it was time to let the relationship go ?

We’ve been together 5 years, 2 babies, we live with family to save money, if we split up neither have another spot to go to, I can’t let go of the fact he cheated. I never wanted to imagine him with another women but I am miserable 😭 I am starting school soon and I am afraid as soon as we split he won’t be in the kids’ lives, making me a single, full time working and full time student.