I wish they would break up!

I have a mad crush on a guy but he's seeing someone else I want them to break up so bad I find myself stalking them every day every hour every chance that I get. I'm being so obsessed.

It really hurts my heart and I don't know if I can wait for him. He knows how I feel and he said I should just wait bc he claimed he doesn't really like her and they'd probably wouldn't last long. But from what I see their relationship is still strong.

What should I do?