I did what you guys are talking about and the feeling is oh-so good!
Let me explain. I was going out with this chick from Febuary-March to the end of april. At the time we started dating, I haden't been in a gym for over 1.5 years. A shoulder injury and other personal problems led me to depression. For 1.5 years all I did was smoke weed and pop pills. When I got up to 210 lbs at WELL over 20% BF (at 5'8), I had a 41 inch waist, and I finally decided to get back to training.
When I started, I swear I could not lift the fucking bar! I trained only my shoulders up until April to get them strong again. One day in April, I woke up, and I was able to bech 165 lbs for 8 reps. It may have been a warm up for me a year ago, but that did it, I was hooked again. I started enjoying the pain of training again and started to train twice a day. My diet was so clean it was almost sick.
She started to nag me. Why are you eating this, (the bitch use to bake cookies), why won't you eat my cookies, why can't you go out, why don't you spend more time with me...and it goes on and on...
At the end of April, I was 180lbs at with a 34-35 inch waist. I was going to start bulking. Now that I was eating her cookies, she complained, why are you eating so much, 2 weeks ago you weren't eating anything, you're so full of contradictions! You are going to get fat! why do you want to put all that size on it's all fat anyway! I told her I was going to put muscle on with fat and then diet off the fat: she said bullshit, it doesn't work.
Finally, she made me choose between BB and her, guess what I choose! The only problem was that she sat in front of me in my law class at school. What a pain that was.
Anyway, summer started and I stopped seeing her alltogether. After my bulking, I was up to 200lbs, but pretty flabby maybe 18%. But I had added so much of my muscle back. I got down to about 194 through dieting and my waist was about 36 inches.
What was my point again? Oh, one day I came into a pharmacy near my gym looking for a gelpack. I had just trained, and was fully pumped. There she was at the cash! She couldn't even keep her mouth closed when she saw me, she started to stutter, and couldn't even hide her amazement.
Man, I can't describe the feeling of satisfaction that gave me.
This post is very long, so I'm sorry, but the best thing for you is to use that frustration to drive you to become a monster. One day you will see her again. I can promise you that: things have a way of working out.
(Btw, I'm now 190lbs with a 35 inch waist, I did all that naturally.)