"The man you and your best friend share a crush on may have a crush on you" ... Yeah that's always an awkward situation.
... Amber Does have some kinda crush on Max right? I can't really remember and there's nothing mentioning it in her section of the cast bios. She should have indicated some sort of interest in him otherwise it wouldn't be this awkward in getting out already.
Yes, Amber's been crushing on him since pretty much day one.
As for Rebecca... I get the impression that, due to past experience, she just ASSUMES any boy she's interested in will only have eyes for Amber. Whereas Amber remains blissfully unaware of Rebecca's issue.