What should I do?
Did You A Favor.
What's unfortunate about long-distance relationships is that good people can appear to be disconnected. I am unsure how to read this man's actions, whether they are as shady and disconnected as they seem. On one hand, he was seeing someone else, while with you. Do you think this was a new way of seeing people, something that you have to accept? I know with online dating, there is this norm where people talk to many people to try and understand which ones they want to actually date.
There are many pieces to this that could contribute to your thoughts to either end it and move on, or stay. The thing that pushes it over the edge for me was that he broke it off. I know you said you still want to see him and talk face-to-face, but why? What are you realistically expecting to do face-to-face? What can you offer, and what you are willing to offer? Is it good for you? What I am saying here is don't be willing to go further than he is in this relationship because it will drain you.
I understand finding someone we connect with isn't as easy as it sounds, but settling on someone who is far away and who dated someone else while you were considered together, are those the characteristics of a man you want to be with? Does being with him prevent you from meeting anyone else? If so, that is the problem here. This is why people still talk to someone else while they online talk to another, to make sure they aren't missing any candidates. I am not condoning this, but rather acknowledging how some people internalize and act out something now normal when we might see it as a personal thing against us. From that, is that someone you want to be with?
You did have some opportunities to talk face to face, and either you didn't (such as in November), or you waited until the last minute. Either way, these issues you speak of, why were they not the first things talked about? Was he allowed to control the narrative and therefore didn't want to address it? Did he have to leave conveniently and then break up (too correlated for my taste)? I think he is showing you his true self, but I think you think this is all you deserve. Do you realize that you could also make calls in this and have him respond to you? He could ask you, "are we good?" But he isn't, and you are just left to chase and try to make it all better.
Again, I don't have all the details, but from what I am noticing, you are giving too much of yourself away, and it will end up causing him not to respect you and you not respecting yourself. There are worse things than being single and being with someone you give up everything for; that is worse because it's you giving up on yourself, giving him too much say over your life. Those relationships and that power dynamic do not work, happily long term.