My girlfriend said she had something to tell me and wanted to talk in a quite spot (we are currently overseas on holiday), she then proceeded to tell me a lady (30F) showed up to her work asking for my girlfriend because the lady's partner (35M), who my girlfriend works with has gone on 4 dates with my girlfriend and the partner hasn’t come home after 2 of them. I trust my GF and know she’s loyal and hasn’t been on dates with the guy. The guy has been helping her and her family with some construction work around their house such as fixing the water mains when they were leaking.

I know my girlfriend didn’t cheat on me and isn’t a home wrecker because I trust her but I was quite shocked when she told me as I got cheated on in my previous relationship. I blurted out “are you a home wrecker?”, this was intended to be more of a joke and not an accusation. Immediately after she smacked me on the shoulder and got visibly upset, I also felt upset because she smacked me out of anger.

Now she has walked off and said she will meet me at the hotel, we are currently on holiday and will be leaving in a few hours to fly back to our home.

I tried to explain that I do support and trust her and I’m not sure why I blurted out that question, I am also trying to let her know I was upset from the smack but she wasn’t listening as she said I was making it all about me, because I’m not understanding how she feels about the whole situation since she could even lose her job and I was accusing her of being a homewrecker.

I need some advice on how to navigate all of this?

Tldr: GF told me a lady came into her work looking for her because her partner has been going on dates with my GF. I blurted out asking if she was a home wrecker and she got mad at me while we were about to fly back home. Need advice on how to navigate this?

Update: Didn't expect this to gain so much attention. I just wanted to reword a phrase in my first paragraph. The lady went into my girlfriends office to ACCUSE her of going on 4 dates with her partner.

Also, I have been in a relationship with my girlfriend for 2 years and she lives at home with her mum and brother. Her mum doesn't let her stay over at anyone's house unless my girlfriend is going on a roadtrip/travelling overseas.

I was also cheated on in my previous relationship so when I blurted out "Are you a homewrecker?" was a bit of nervousness, joking and apprehension. Myy girlfriend got upset with me because to her the tone in my voice was me accusing her when I asked the question.