Should it be a dealbreaker if he doesn't call when he says he will?

Anonymous
My boyfriend is generally great. But he has this habit where he'll say that he'll call me or that we'll meet at a certain time, but doesn't actually do it. He'll either not call at all and never acknowledge that fact that he didn't call me, or message me a few hours later to reschedule. I feel silly for making this such a huge deal, but it just makes me feel like shit when this happens. It's just the way I learn to trust someone in general - whether or not he/she does what they say they will do. My boyfriend has always been this way even before we started dating, and I think it's just who he is. But I really hate it and feel like I can't trust him if I can't even count on him calling when he says he will.

Do you guys think I'm overreacting? I always want to break it off when this happens, should I do it?
Should it be a dealbreaker if he doesn't call when he says he will?
2 Opinion