I wouldn't put too much significance on your initial experience with the singer. She might have felt tetchy for any number of personal reasons (including biological) and that icy stare may well have been totally out of character for her. I'll never forget my first couple of weeks at a new school when me and this other kid REALLY rubbed each other up the wrong way. I remember staring at the back of his neck in class thinking "God I hate you so much." A couple of weeks later we were best of friends. As for political differences, it wouldn't even bother me if she was a Trump supporter or anyone else I didn't like. I have a good friend who's a Marxist and I'm like almost the exact opposite of everything he believes in and yet we get on great because we know when to avoid the subject of politics.
My only worry about joining a band now - and it's been almost 15 years - is perhaps damaging my ears. I hate to say it but I'd be pricing out those fancy fitted earplugs.