Long post..trouble with memory

Long post, but please read. This is reposted from another forum. Need answers because my OCD is going crazy with worrying that I could be going crazy!!

Short version: I have a vivid memory that has most likely never happened to me. What is the cause for this? Trouble discerning a possible dream from reality.

Long version:

Awhile ago I was feeling guilty for all the compulsive lying I did in middle school. ( I am 21 now so this was about 9 years ago). I was very insecure and did this thing where I made fake social media accounts and talked to others behind pictures of random pretty people I found on the internet. I was young and stupid. I since then deleted all the accounts and have gotten better with the compulsive lying. I still have low-self esteem, and I have the diagnoses listed on the bottom of this post.

Anyway, the other morning I woke up with this vivid memory of me browsing facebook two years ago and coming across an account that I must have forgotten to delete, because it used the same picture I used for one of my other fake accounts. I remember the name of the profile being Jade Rydall. So I clicked on the profile and realized that I didn't remember making any of the posts that were shown on this page's wall- but the profile must have been mine because the location of this profile was in the small town where I was located when I was making these fake accounts, and because it used the same picture that I had used for another fake account. This picture was one only I would have had access to, because the real person the picture was of was someone I added randomly on facebook for the purpose of using their picture, because I thought she was pretty. Also, no one else in my extremely small town was doing this kind of horrible thing at that time except me. Anyway, I saw this Jade person's profile, knew it was fake, knew it was from my town and saw they had talked to people on their wall that I knew, but I had no memory of making it. I really wanted to delete this profile, because I knew it was one I had made back then even though I didn't remember making this particular one. But I couldn't think of any email or password I would have used to make the account, so I never was able to log in and delete it.
That was the extent of my memory.
So recently, as I remembered this randomly one morning just upon waking up, I decided I would go on facebook again, look for that account, and see if I could remember any password I would have put it under so I could delete it and therefore forget about that horrible part of my life. So I went on facebook, searched Jade Rydall, and nothing came up. Hmm. I typed in Jade Rydell, or similar names, just in case I remembered it incorrectly, and nothing came up.
I replayed the whole memory again and the thought popped into my mind "what if I dreamed that whole thing?"
I've never actually remembered something accurately in my sleep, like I seem to have done with this memory... No actual evidence of this profile ever existed... I became so worried I was delusional and going crazy that I sought help immediately.
I told my therapist about it and she said that facebook profiles do not get deleted unless someone reports the account or the user deletes it. I never deleted it, I never reported it, and since the activity on this account would have been about 10 years ago and I "remember" viewing it 2 years ago still, I doubt anyone else would have realized it was fake and reported it so recently. So she concluded that she thought it must have been a very vivid dream, since I have been having tons of vivid dreams lately. There was nothing bizarre in the dream I would have been able to look at the scenario and say "not real", and also it tied so perfectly in with life events that actually happened to me, such as the same picture as my other fake accounts, it being located in my hometown, etc., So she ultimately thought I suffered from OCD and also a depersonalization episode..not psychosis.
But a few weeks passed and I couldn't stop thinking about it. My OCD wouldn't let it go because it felt like such a real memory and I couldn't stop worrying I was going crazy because I honestly didn't know if it was real or if it was a dream. I realized there was one more thing I could do: I could check my facebook search history. It would show me any profile I was on, and if I really did see this profile, it would show up on there.
I searched by facebook history for exactly 2 years ago and there was the name "Jade Maydall" on there, in between two other names that I am familiar with. The other 2 names showed up as links to the person's profile, and the Jade name had no link, it just showed that I had typed it in. So wtf am I supposed to think now? I do not know anyone named Jade except in this inaccurate memory/dream. If there was a profile, it was deleted by now. If there was never a profile, then it's a freaky coincidence.
My therapist does not find it concerning and has not changed my diagnosis to anything related to psychosis, but I am having so much trouble discerning whether this is a real memory or a dream. I feel like I should know!

Does anyone have any advice or help to offer me? My OCD is running rampant over this