Boyfriend cheated?

We were together for a year. An old neighbour reached out at the beginning of January and he responded. They communicated for 4 weeks without my knowledge. I found out that the night we broke up, he took her out for dinner. He came back the following week wanting to work things out. I have spoken to the “neighbour” and while it sounds like he lead her on for a few weeks, he’s doing everything he can to fix what he’s done with me. My mind is numb and i am not thinking straight! Please let me know what you think.. Why wound he do this? I know men and woman operate differently in terms of “communicating with the opposite sex” men generally want 1 thing whereas woman tend to want more. Help!
Boyfriend cheated?
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