Possessive girlfriend (26) keeps torturing me (29m) over smaller and smaller issues.

So I?ve been seeing my girlfriend for almost five years now. As with any relationship of that length, we have our foibles and occasional fights but generally things are good as there is often no reason to fight.
Ever since I?ve known her, she has always had a possessive streak and I?ve tried my best to accommodate this tendency in her because I value her and the relationship. In the past she has spied on me (checking emails etc whilst I?m buying her breakfast) and has always questioned my motives for doing very simple things (e.g. if I go to the bar with some grad school class mates, then it must be because I want sex). I?ve always found this frustrating as I feel that I shouldn?t have to justify every single activity and because I am ultimately innocent and not acting suspicious.
To her though, even the most innocuous things arouse immediate suspicion and fear. Today, I feel like giving up after a recent argument which came about because of this. An old female classmate of mine from a master?s degree added me on FB after I made a new account (I got off the grid a while ago but found that I needed it again after moving to a new city/university). I haven?t spoken to this girl in two years and I still haven?t. She is also in a long term relationship herself and my girlfriend was previously aware that we had a friendship when we studied together (it was a constant source of anxiety for her).
Now that my girlfriend found out that she added me, I?ve been getting grief all day because I ?must?ve been hiding something?. I am not hiding anything and I try to explain this to her calmly but she doesn?t listen. She says that because I didn?t immediately screenshot the friend request and send it to her, that I must be hiding something or that I must ?need a lot of privacy?. I don?t think I?m being unreasonable in getting fed up with this behaviour, I love her and want to be with her, but these games are driving me away.
What can I do?
TLDR: I don?t want to keep appeasing my girlfriend?s possessive behaviour but I do love her and want to stay with her. Is there anyway out of this pattern?


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Hey everyone! Thanks for reading im a newbie here!!! Well I simply want a bit of advice really... I met a guy in hospital in 2020 whilst i was after having my lil boy. We became quite good friends... he also sufferd bpd. he seemed to cope well and had never been medicated before about..Well one day (during relapse altho i was trying to help him through it) she got a bit confused about something that happend with me n my mum.. which was also about... for some reason this made him flip out at me as he assumed i was lying etc... Id simply tryed to explain to her what was happening although my cash had nowt to do with him. But we stopped talking.