Should I Drop Them?

Drop.

People like that are super clingy and it doesn't really matter if it was a girlfriend or just someone else you spend a lot of time with. They get jealous of anything you do that doesn't involve them and try to actively sabotage it so you'll come back to them.

 

I agree, you should drop your "friend" - If she cannot be happy that you've found someone you really like, she's not a true friend. And like Destin said, she will try to sabotage it so that you keep coming back to her. I think your friendship with her has come to an end, and it's for the best. Some people just weren't meant to walk our whole journey beside us. Cut your losses and move on and be happy with the girl you like

 

Looks like your relationship with her is toxic. Better to end the friendship.

But maybe for your sake ( since you say she is special to you) you can sit her down and talk to her. Tell her that being in a relationship will not change that she will always be your best friend. That you will try to spend your time equally with them both. You will not ignore or forget her.
Maybe she is just feeling insecure.

But after all that, she is still behaving badly towards your crush, well good riddance then.

 

Move on.

You do not need that sort of negativity in your life. If she chooses no to support you on your journey, drop her at the next stop.
But I agree with Cas girl, talk to her.

 

She doesn't sound like a true friend and I would move on.

 

I have to agree with everyone that has posted. But I do second sitting down with your friend and talk about it.