So my question is if I complete this quest for Molag Bal can I still do the quest for Boethiah???? Cuz I know I really want the ebony mail....

Yep, I did that. I guess Daedra Lords are fickle beings haha

Sweet then I guess its time to finish this quest then get lydia wasted and lead her to her death!!! Guess u should have been a bit nicer to me when I politely asked u to carry all my stuff!!!!