Not safe around couples?

On a note related to being a 'party animal' as would have been said ten years ago by some spaced out West Coast USA 'dude', I appear to be a threat to couples. This is rather rubbish for me because it always makes half of at least one couple in any group I go out with rather distant - they're trying to act indifferent and nice but seem to think that I'm a threat to their security. I don't know how this happens, and it makes one rather alienated anyway so it's an unpleasant situation. Perhaps because I'm younger than most of the boys I'm out with, the older guys feel threatened? Whilst out last night there were two guys there and one of them seemed like he was a lot of fun, dancing manically and having a good time. In the meantime, the other side of the couple was clearly having a bad night, being rather grumpy and unapproachable. Aware of this, I deliberately didn't dance with his boyfriend but stayed with the rest of my group, just dancing as a group. It didn't improve. Maybe if I had danced with one of them it would have given the impression that I wasn't a risk to them, but it could have just made one guy feel even more defensive. I wasn't a threat, they're together, I'm not going to try and break that up, I'm not like that.
I just wish people would stop thinking that I am.