I don’t know what to do!

My ex and I broke up. We have 2 kids and of course living together. I found out he was going to stay the night with some girl so I left and moved in with my sister. It’s only been5 days and she’s already telling me we have to leave. The only option literally is for me to go back to my kids dad’s house and he’s going to be so mad. I don’t want to be there either. But I literally have no option. I’m so fucking pissed and upset. I don’t know what to do.

Life wasn’t made for me. It really wasn’t.