<human>: Can you condense the text into a few key points?

So my girlfriend and I are at university together and she went off for a week in March for some work experience at a company. 

This morning she left her phone open on her Twitter direct messages while she went for a shower and I noticed messages between her and the person who gave her work experience about how'd like her to go back again, and there would be plenty of "extra-curricular activities" like last time. She responded positively with a wink emoji and the conversation continued. There was nothing explicit, literally just teasing.

I questioned her about it (obviously apologising for "snooping" on her messages) and she said that they didn't do anything, it was just some verbal stuff (he asked her about her qualities, she replied "I'm good with my mouth"). Apparently he started it but she reciprocated the chat because she thought she'd get a job out of it. 

She's apologised and been in tears and swears that it went no further than that but I'm finding it hard to trust her, and am really hating the fact that she spoke like that to someone while we were together. 

I feel sick about it all and don't know what to do.
<bot>: My girlfriend talked dirty to a potential employer to get a job, swears it went no further; I'm really hurt by it.