new to this site, but not new to this feeling. any advice?

hey guys, I’m new to this site. two years ago I experienced derealization, I felt I was just dropped down in this earth, everything, I mean EVERYTHING terrified me, from my on conscious to literally living. I didn’t know what to do. eventually I got over it, I think Injust accepted the feeling and moved on. I have pure o ocd so I’ve been suffering with that and just recently I’ve experienced the same feeling I did two years ago! I feel like I was dropped into this world with no knowledge of anything and everything seems unfamiliar! It terrifies me! nothing seems real! but this time I have this feeling that creeps up on me that makes me feel like I want to suicide. I’ve never been suicidal, it’s more a feeling than thoughts. no, I do not plan on doing it. I don’t know if it’s because I feel trapped in this world due to derealization that makes me feel like that’s the only way out. but deep down I know that’s not what I want to do, but every time I think about the future I can’t see myself there! and since i’ve had this feeling, life seems so long and dreadful, derealization makes everything in my life seem so complex and scary! again I have pure o ocd, so I don’t know if my pure o is making me feel like this since i’m derealized. but I just wanted to ask if anyone has had a similar feeling?