She left and has been sleeping with another guy, 40 days later I got drunk and kissed one of my friends and feel awful/confused

Last night I went out with a friend, and we drank… a lot, and ended up making out. It didn’t go much farther than that, but the amount of shame I am feeling is palpable. She says we don’t have anything to feel guilty about, that my STBX has moved on and it was fun. On paper we are still married… we are still married and I feel I have stooped to her level, lost some ground. I still feel committed to my STBX, even if she isn’t committed to me. I still feel like I am in that relationship. Even if I’m not, even if she has moved on, my heart is still there.

Our relationship is dead, we are over. We still exist on paper, we are just waiting for our court hearing... but she has been gone for some time, and by all accounts is still sleeping with the other guy. It has been 41 days since D-DAY… waaaaaaayyyyyy too soon for me to be messing around with anyone else...

Was that cheating? Logically I don't think so... we are done and she has moved on to someone else.. but I am so scared of becoming a cheater. I am so scared of becoming that. I have a tendency to dwell in shame to the point where it does more breaking than building.. Even when I was single I didn't do a lot of hooking up, so a large part of this is my wrestling with going against my own values...

I'm not really sure what I'm asking for really, I just feel scared tbh.