What can I do to regain trust and break myself from that part of our story and move on with him?
I can understand your concerns, and you’re wise to consider what your history together means for your future together. There’s a difference, though, between dwelling and examining, and I would encourage you and your boyfriend to examine your fears about the affair that you both were a part of. “Freaking out” and obsessing are simply forms of anxiety, ones that go away once the anxiety has a more productive outlet, like an open, honest dialogue.
This is why when someone cheats, it’s important to understand why they cheated and what they learned from the experience. While some research shows that people who cheat are more likely to cheat again, it’s also the case that more than half of those who cheated before aren’t repeat offenders. Sometimes cheating is related to problems in the relationship—not just things that aren’t working, but the fact that the couple isn’t talking about the fact that they aren’t working. Sometimes affairs are about something in the person’s psychological makeup—issues with intimacy or attachment. Sometimes people have affairs in response to a life-altering crisis: after the death of a loved one (a parent, a child) or in the midst of a partner’s serious illness.
In your boyfriend’s case, even though you two have a strong connection, it sounds as if the affair was at least partly related to his ambivalence about his relationship with his girlfriend. He felt paralyzed, unable to decide whether he wanted to be with her. It may even have been the search for the house that forced him to acknowledge whatever questions had been percolating.
That’s all understandable—many people have doubts about their relationships, and better to discuss them before buying a house together. Maybe you can even have some compassion for what he went through—how excruciating it must have been for him to have so much invested in this relationship, to be at an age when people are planning their futures, and to wonder whether his partner was the right one.
But then there’s this: Despite his fear of making a decision he’d regret, despite his not knowing for certain what he wanted to do, he wasn’t direct with you about his confusion. He didn’t say to you, “Hey, I know there seems to be something between us, but I’m in a relationship and I need to figure that out right now. If and when I do become single, let’s see where we both are.”
To understand more about how your boyfriend handles his feelings, you’ll want to get a sense of what was happening with his then-girlfriend, too. I don’t know what he told her about why the house search was called off, and I wonder how the two of them dealt with this. Did they talk about his ambivalence? Or did he choose the path of avoidance—“Work’s really busy now, so let’s resume the house search in the new year”? Meanwhile, when the two of you were “talking” at work, what were those conversations like? Did a lot of the conversation revolve around his complaints about his girlfriend—issues that should have been discussed directly with her?