I'm going out with a girl on Saturday who I've already got pretty far with. The issue is that me (Being an idiot) message her about things in a group chat where we have a mutual friend who is never online.

Today she hopped on and simply invited herself out with us. The girl is too 'nice' to put her foot down and I'd face a lot of social backlash for telling her to sod off. I'm tempted to just tell them I can't do it and go out with my friends for the night instead, but at the same time I do want to make some progress with the girl which is going to be super difficult with the friend there.

Maybe I'm just looking at this wrong and it's a chance to learn to progress with women in a group of people?

What should I do lads?