How long has it been since the split? Has it been amicable?

Anyway, it seems quite clear from what you wrote that he has effectively moved on. It might thus be best for you to have a break from one another for a while. You need time to heal and you still seem vulnerable on this aspect. It is not easy to get over a break-up and i don't think it is healthy for you to put yourself in such situations where you feel left out/abandoned etc. Because the end result is that *you* will get hurt. And seeing him thus will be like sticking the knife in the wound. You don't need that.

Also, he seems to be quite rude if you went to him for help and he seems to have basically ignored you. You should move on as well, pick up the pieces and move on. It will take time to heal, but for your own good, try to have an identity and a life, apart from him...