I know lads that go out on their own with the goal of pulling women. They’re usually pretty good at pulling so they don’t spend much time actually on their own though.
If you feel sad, it’s more in your own head then anyone else thinking it. If you went into a fairly busy bar and sat down on your own, I doubt anyone would notice, never mind care, that you were on your own. It also probably is a good way to chat up birds and go wherever they’re going to go next I imagine.
If you think about it I suppose, if you're only out with one mate on a given night and one of you gets chatting to a bird, the other one spends plenty of time on their own (if they dont get chatting to one aswell) anyway.