<human>: I've been seeing this girl for a while now, and we have a very solid relationship- we like each other a lot, and we care for each other a lot. She's been away for a couple of months of vacation now, and today I went out with an ex-girlfriend (old friend of mine) to grab some lunch. I told my girlfriend beforehand and I went to have dinner with the ex before and everything was fine.

Today, however, it was very flirty and even though nothing really happened, I still feel as though I was emotionally cheating. She put her head on my shoulder at one point but it was very brief and I moved away, and we (sort of) held hands for a second as well. I feel like it is nothing substantial that I would say, but it definitely didn't feel like something purely platonic friends would do and I know I would be upset about it. 

I think it bothers me because I know that even though nothing happened, I explained to the ex girlfriend I am in a happy relationship and I would never cheat, I was attracted to her and I did want to do something. I am not sure what I should do- I won't be seeing the ex girlfriend again, of course, and I will avoid any situations like that in the future. I just don't want to tell her if it's only to make myself feel better; that seems a little selfish to me.

Can you give me a shortened version of the text?
<bot>: met ex girlfriend, flirted a little, felt uncomfortable because I felt like I was tempted, not sure what to do??