How do we get through this? How do I heal?

So about two or three months ago, my boyfriend did something that completely broke my heart. I'm not giving details, but it was complete betrayal. We are seperated right now, "working" on things, because he wants this to work. He said that I can take as long as I want and I am trying, very few things have improved, but this thing he did, it still hurts. In order to even give this relationship a shot, I need to heal from it. And I am willing to give it a chance, but I need to know how to get over this. I have been trying for so long and I don't even know where to start. Any ideas?