Living in B-E-A-UTIFULL San Diego...

I'm 20 years old, and I'll be celebrating my 21st birthday in about 5 months. I really would like to be back to the weight I was in high school, so I guess I have plenty of time. The "freshman 15" turned into about 30 for me. So I want to be walking down the beach in a bikini, and I sure do want to turn heads with what used to be a sexy body. I go to the gym three or four times a week, and every time I weigh myself, it seems like I'm gaining weight. Someone suggested that it may be muscle forming, but I wanna see results! :( Anyways, I'm looking for friends to motivate, and to hopefully motivate me to get the weight off by summer!