Break up

Me and this guy had been dating for 9 months and it was all perfect! Out of nowhere on Sunday he sends me a long text about how I'm boring and he hasn't wanted to see me for the last few months and he's unhappy. I said we should just break up then. I don't understand. The same day he started talking to his ex, she was logged into his Snapchat and everything. I asked him about it and he said that he messaged her to see how she was doing and she had a boyfriend. I WAS almost certain that he would want me back here in a few weeks because when he stays on base he gets bored and depressed but now he's talking to her again. I don't fucking know. He also did this right after I found out my mom has congestive heart failure and is very sick and also had a death of a close friend (day after). Seems pretty shitty