Most Helpful Girl
She has a boyfriend now so you have no chance... for now
Most Helpful Guy
No she won't take you back, leave her alone.
You're behavior is typical of a selfish and immature person. "I told her I wanted her to be my girlfriend, and that I really liked her" - So why did you ghost her then?
You took her attention for granted and now that she's moved on, you're jealous and want her back - Not going to happen, you had your chance.
You don't do anything, you leave her with her boyfriend and find someone else and I suggest not ghosting them this time.