Is it possible to forget you’re an alter? / Could my trans identity be linked to an alter taking over?

Hi there! I hope its okay that I post this here i just didn't know where else to ask this stuff, feel free to tell me to delete this if this is wrong here :). Its been in Discussion quite some time that I could have DID. My therapist has been talking alot about the possibility for years but I have no Diagnosis yet. I'm a Afab person and as a child I always had this separate guy in my head. He was a completely different person I could talk to, he often influenced me and his thoughts and descisions were completely out of my control. This same guy followed me all my live in my head on a daily basis starting around age 7/8 until I was about 14/15. Then he suddenly stopped existing and stopped talking to me and everything. Me and my therapist always just assumed that I was starting to develop DID but never fully developed it, hence why that guy disappeared. Now today I had a talk with a friend who kinda made me realize smth. Around the time the guy disappeared I started having gender issues. Before that I never had any issues with being afab but around that time I started to develop dysphoria and started to feel like I am a man. I've been identifying as a transman ever since. This friend asked if it could be possible that the guy that was in my head as a child didn't dissappear at 14/15 but instead fronted and that this is the person who has been actively controlling the body ever since then. My therapist over the years also kept talking about that she had the feeling smth in me "died", like a separate part of me. This is freaking me out right now. Is it possible to forget you're an altar and is it possible for the core to dissappear? And that for multiple years, as I am now 19. I'm sorry if my terminology is wrong feel free to correct me im still really new to all this. I will definitely talk to my therapist about this too, but I just wanted to ask other people who may have experienced smth similar or know more about this topic then me.