Help!

I’ve been really struggling these past two weeks. About 3 weeks ago, I introduced my best friend to my other really good friend (who is also the guy I kinda like). A couple days after they met, they started dating. It made me very sad obviously, but there are so many things wrong with the relationship. 1: my best friend, C, is so young. She’s my little brothers age (just turned 14) and my guy friend is my age (almost 16). I know that’s not a big difference but she’s too young to be dating. 2: her mom doesn’t allow her to date, so she’s going behind her back. 3: they barely know each other, so it’s all based on looks. 4: they use me and my house as a place to meet up. I told my mom about it because I don’t know what to do. Should I tell C’s Mom that they’re dating? Or keep helping my friends lie to their parents? They both know I don’t support the relationship, and I can’t make them do anything. This whole thing just has me so stressed. I’m emotionally and mentally worn out.