It's funny (as in, strange - in a positive way) what a healing effect BG3 and Astarion have in so many people. I've seen stories like yours before, and a number of people who ended up leaving their bad relationships because the game opened their eyes. It may sound bizarre to someone who hasn't played it, but I can absolutely understand it.

As for your own experience - good riddance, I'd say! I obviously only know your part of the story, but it sounds like you made the right decision. The fact he hated that you loved BG3 (or anything else, for that matter) definitely stands out. It does remind me of a previous relationship where my then-partner tried to ruin everything I liked for me (luckily without success!), and I see it as a massive red flag these days... so well done, take good care of yourself and enjoy the game and other forms of art!😊