brother, i am giong through the same situation, i thought she was the girl of my dreams, and now i still get sad on occasion when it floats back, but heed my words brother, this could be what you need to make your life BETTER, yes this pain can be utilized for success.
Earlier this year, i was heartbroken and to get over it i trained till i wanted to puke.....and since my existence depended on my training , all thoughts of the girl went away. Now im doing the same thing again, i get up at 650, run away my nightmares of her with 4 miles......then i go to work to keep occupied, then i come home and i train like a mother****er on kickboxing. Feeling the pain i feel from her makes me want to be the best all the more. Whenever i feel like dropping dead at the gym i take that pain i feel and i use it as motivation and i go on and on until someone is beaten senseless or i pass out. After i push myself to the edge in training i feel like a million bucks.....the only bad part is thoughts come back when you arent occupied.......so STAY OCCUPIED. I do martial arts as my outlet, but you put that hard work till you drop philosophy into anything, my one freind who was in the same situation put it into his music and hes gonna hit the bigtime cuz his game improved that much through that hardwork built on pain, just like me.
I would not reccomend dating other girls right at the moment, cuz im trying to do that, but i feel nothing for any of them. Take time off women and dedicate your body mind and soul to your passion in life and then it will all become better my friend.
Keep up the fight and dont ever quit.
PS. No matter how much it hurts to see her or you want to talk to her ........ DONT. its gonna hurt bad, but just dont..... if you have to be near her or see her often, smile or somthing and KEEP walking...... if she initates convo, keep it short, BUT POLITE.....and LEAVE...... if she truly wants you back she will keep initiating once she finds out you are beyond her..... but NEVER initiate, then it is up to you if you would take her back or move on....my best advice is move on cuz it will never be the same ... its very very tough brother, but im going through the same thing