Tell them. The sooner you tell them, the better off you will be, in my opinion.
Now, why are you so worried about making your parents happy. This is your life, not theirs, and who you devote your love to, in any form, should meet
your requirements, and be true to
you, not your friends. If you don't have any guy friends that you want to date, then why do you want to in the first place? I do not expect your parents to be angry that you don't have a boyfriend, because you do not want them.
This is not their happyness. It is yours.
As for your crush. Your crush is taken, and should be considered off limits, in my opinion. Why? Because she has someone she is happy with. If it turns out that she wants to be with you instead, then so be it, but if she's found someone she likes, I'd say stay away. Why? Because you wouldn't perticularily want that to happen to you, in turn.
Cheated the way from fringe to elite. Clique of stylists, rounded illogic skipping a beat to a dead cert. By lheaving charges and bursting the abscess, with a forked toungue, bloated with courage and spewing self-importance. Drop your sights, aim lower, leave umblemished those with real power.