<human>: Context: I've (M/27) been going out with my girlfriend (26) for 2+ years. We're very happy together, even if she doesn't understand my love of sports and her used my razor on her underarm hair on more occasions than I'm comfortable with.

One of her best friends is the titular lesbian (31): a very lovely lady who, as long as I have known her, has been chasing skirts like any young (though a couple of years older than me) romantic should. They're quite close and have been for the best part of a decade.

But recently (last 6 months) they've been in contact slightly less than previously. She and I have very similar interests and have been texting back and forth about a festival we've arranged to go to this summer, one my gf has zero interest in, but she doesn't mind the two of us going together because, y'know, trust.

Anyway, we've been in contact a lot over the last two weeks since tickets went on sale, organising transport, accommodation etc. Her texts/calls have become noticeably more playful too. Then today, out of nowhere, she texts and asks if I want to come out for drinks this coming weekend. This set alarm bells ringing because a) she knows my gf is out of town and b) she doesn't drink. Luckily, I've to go away on short notice on business this weekend, so I didn't have to make up an awkward lie, but now I'm really concerned.

**Question:** Should I tell my girlfriend? Should I contact this girl, be upfront and ask her motives? Or am I just reading way too much into innocent signs and misinterpreting them? I don't want to ruin a decade-long friendship if it can be avoided at all costs, and no way would I consider cheating on my girlfriend. I care about her too much for that. The prospect of this festival is worrying me now too.

Give me a shortened version of the text
<bot>: I think my GF's lesbian friend asked me out. Am I misinterpreting her intentions? If not, what should I do?