I am confused

I recently ended a two-year relationship with my now ex-boyfriend, and I’d like to hear others' opinions because I’m feeling very confused. I’m not sure exactly where to start, but I’ll try my best to explain the situation. It is my first relationship that lasted years btw and my ex boyfriend had history of depression, just an info for better understanding.

So yeah for the most part, our relationship was fine. However, things started to change when I went on vacation. I was extremely busy traveling and, while I still communicated with him, I wasn’t able to give him as much attention as I normally would. We used to call each other every day, but during my trip, it became difficult to maintain that routine. We didn’t have any calls for about three or four days, partly because of my hectic schedule and partly due to internet connectivity issues.

When I returned from my vacation, we finally had a call, and during the conversation, I said something that I meant sincerely, but he seemed to interpret it differently. He then started bringing up things from the past that he was upset about, things I wasn’t even aware had bothered him. The conversation got pretty intense as we both started sharing feelings and grievances from the past. It was clear that we were both hurt and confused. We decided to end the call and take some time apart to think about everything. The next day when we talked again, he confirmed that we were breaking up.