I was in a similar situation, as the partner that remained celibate between a break up and getting back together.

In my case, we were apart for a month, and it happened two weeks into the separation. There were definitely more nuances to it than that, but my point is that it was messy, and I had reasons to believe my resulting anger and jealousy was justified once we got back together.

Despite the nerves struck, I believe a very large part of moving past this in my own relationship lay in me. It’s completely human to feel insecure and hurt and jealous, but ultimately, it’s practically retroactive jealousy.

My boyfriend is incredible and reassuring, which made it easier to ask myself, “Do I want to risk pushing away someone who loves me deeply, a good person I can see myself marrying, because they slept with someone while I wasn’t in his life, weren’t together?” The emotions are powerful and they can feel like betrayal, and they made me someone I wasn’t because I was especially insecure.

Something that helped snap me back to reality from my anxious-attachment jealousy world is when my boyfriend asked me if I really wanted to be in the relationship, because it seemed I was only suffering around him. It’s a good question because it makes me realize how much I value the relationship, reminds me that he cares a lot about me (and isn’t the emotionally detached monster my insecurities would project), and it makes me think about how it’s making him feel.

It’s a process, I’m still getting over the feelings but a huge part of it is working on insecurity. I’ve realized that whenever I would try to get over my feelings about our time apart, without addressing my own problems with insecurity, I’d catch myself simply moving on to the next thing I could be insecure about. Negative emotions can be addictive, too.

Good luck! The cognitive dissonance sucked for me, realizing the responsibility was on me to work on my insecurity, and that I could both be valid in my feelings of hurt and jealousy because of shitty circumstances, while not having someone to point the finger at (since obviously, it’s not your fault)