I wonder if I'm at all responsible for ditching a friend during the peak of an lsd trip. He's now a woman.
Did you ever ask him if he felt abandoned by you?
Yes, we both talked before and after the LSD trip.
The only way to know if your friend felt abandoned is to ask them. If you have had conversations since and they seem fine, then probably they didn't feel abandoned, but you should apologize if you feel bad about your actions.
I had no idea. I loved him so much and he felt abandoned. I want to help him get back.
It's good you feel remorseful towards your friend. Contact them again to let them know you care and will stick by their side next time. Grow your bond with them and you two will have a mutual trust once more.