Group one is a bitchy group where they appear to be saints to you being 'amazingly nice' when behind your back they are a piece of ****, seen it, experienced it.
Most people you meet in life cannot be trusted, that is a sad fact
I never was into groups or cliques myself.Always had more individual friends,regardless of groups just being myself.
Who says you have to choose?
If they make you choose, then you shouldn't be friends with them.
No one should ever make you choose a group to be your friend. Eliminate that group from your list!