Does this count as cheating on your lover?

So uh this is abit NSFW and I'll put a TW just incase but I've ranted before to ppl that I felt like a cheater for kissing someone else while I was drunk thinking it was my bf but it's actually my obsessive ex. Thing is... It didn't stop at just kissing but it went on that other level AKA sex. I've seen in tiktoks that "even if I was drunk I wouldn't mistake my lover for someone else" but I genuinely thought it was my bf cus I literally got drunk cus I missed him so badly and my love language is physical touch + quality time. Now my bf forgave me for the kissing part but I'm now thinking of adding more details... I feel guilty. I'm so afraid to tell more details cus tbh I did like the sex but when I learned it was my ex I felt disgusted. Abit conflicted cus i still had feelings for my ex at that time like what if it isn't because I missed my bf what if its because the fact I liked him. I don't rlly remember anything from that night I blacked out drunk and I just woke up feeling the worst person on earth.