I've known this guy for a while through a friend. He used to be in a relationship with my friend's flatmate so we all used to hang out at their house, not a huge amount but occasionally. He and I had a hobby in common and we used to say we should do this hobby together, but we never actually did. I wasn't romantically interested in him then, he had a girlfriend who I knew, and he was a lot younger than me, so at the time I had no interest.
They ended up splitting up and she moved out of my friend's house. My friend recently mentioned that this guy was still doing the hobby. I decided to message him and see if he wanted to do it together, still without any romantic interest, I just wanted someone to do the hobby with.
We've now gone together 3 times and I am suddenly interested. I always knew he was a decent guy, we always had a similar sense of humour and similar interests, but now I'm insanely attracted to him as well. The hobby has changed how I see him - he's really good at it and it's very physical so I can see he's in incredible shape. We spend the whole time laughing as well.
If he were my age I'd have already tried my luck. The thing that is holding me back is that he is over a decade younger than me and I'm worrying about it being inappropriate. I'm 39 nearly 40, he's 28 nearly 29. If I knew for sure the interest wasn't mutual, I'd leave it well alone because I'm enjoying the new friendship and the shared hobby. But I'm not sure it's not mutual.
What do I do??!!