He told me he was texting someone else..

We have been in a relationship for 7 years now and have a 5 year old and a 4 month old. The relationship has always been a roller coaster but we have made it through. We have been arguing and a couple days ago he says he hates coming home to me cause im miserable and hes been texting another girl cause he feels lonely and nothing physical happened. Like damn i feel lonely too but i havent went and text another guy. Back in the beginning i was awful and didtalk to exs but as friends and he knows that, im miserable cause nothing i do seems to please him and then im killing myself to make him happy. Im not a fun person anymore. No one messages me to go out, no one messages me at all. Then he says im miserable and goes and talks to another girl for 2 months. I feel like im not going to get over it and even more alone then ever. I dont no what to do.