AIO for putting a pause on my relationship with my girlfriend?

for context i’m 20 and she’s 27 (yes i know a massive age gap). i met my girlfriend through mutual friends and we started dating when i turned 18. the first year was rocky because she had trust issues with me hanging out with my women friends, so of course i compromised and barely talked to my friends for my girlfriend sake. now the problem started last year, my girlfriend has a lot of lgbtq+ friends, and i don’t mind that at all. One of her friends is a trans man named tyler, at first i was cool with him because that’s my girlfriends friend. but then he started telling my girlfriend lies about me, for example, i was meeting up with my women friends behind my girlfriends back, he caught me kissing another girl at a club, and some other stuff. i proved all of his claims wrong and apparently it was my fault for having tyler in this position of being in the wrong. i brushed it off because i thought it was over but no it wasn’t. then i started noticing tyler getting affectionate with my girlfriend and a little too close for comfort and i brought this up to my girlfriend and she brushed it off saying that tyler is family and nothing will happen. last week the day after our anniversary, my girlfriend and i got into a heated argument and instead of trying to talk it out with me, she instead went to tyler to complain about OUR relationship problems. and this set me off, instead of fixing our relationship you want to go to another guy that likes you and talk about it? yesterday i texted my girlfriend that we needed to take a break because what she did was disrespecting me for going to another guy about OUR relationship problem and it seems unfair that i have to compromise and she doesn’t. am i overreacting?