When I was at my work Xmas night out we went to a club and whilst dancing a stranger kissed me. I can’t remember the build up to how it happened other than just dancing as a group. I was very drunk and it took me a few seconds to realise what was happening while I kissed back, but once I did I stopped it and explained to her that I couldn’t because I have a girlfriend who I love (we live together and have been with each other for 7 and a half years). Should I tell my girlfriend? It was a complete mistake that I never intend to happen again so will telling her just hurt her more than not knowing? If it was the other way around I think I’d rather not know than have my trust shaken.