AIBU for thinking my gf cheated on me?

[BlingersMcBling]

I went out on a night out with my gf, we had a massive argument, she stormed off home. When I got home she wasn’t there. She turned up at 6 in the morning and said she’d been with the neighbour and her boyfriend and another lad doing drugs all night. She swears nothing happened. But a few days later she went outside into the back garden and the neighbours boyfriend was outside having a cigarette and I hear him say “It’s our naughty neighbour”.
she swears he only said this because of the drugs she took… but to me describing someone as “naughty” insinuates she maybe did something with this other lad.
she swears nothing happened.
am I being unreasonable for thinking something happened with this lad?
thanks

It doesn't sound like a terribly healthy relationship anyway, so what does it matter?

Sure you posted this earlier today OP. I think you know the answer x

Does it matter? Do you want a childish girlfriend that storms off? Or a girlfriend that takes drugs? Time to move on irrespective of whether she did or didn't sleep with someone.

Why are you posting again? YABU.

Yes I did sorry I just wanted the vote functionality. Posted in the wrong topic, thanks x

Reported for time wasting.

Off topic but is there somewhere that list all these acronyms? YABU/DS/DD I have no idea. Thanks

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