1. Accept your lack of control in the break up. No matter how "good", smart, helpful, giving, or attractive you are, you can't control whether other people stay with you. There are other factors that lead people to leave...and the sooner you accept your lack of control, the easier it'll be to say goodbye.
2. Accept the role you played in your relationship. This may sound contradictory, but even though you are out of control in many ways, you were still part of the relationship! You affected your relationship somehow, for better or worse. There's a delicate balance between being out of control in one sense (you can't force someone stay in your life) and being an active participant in the way your relationship unfolded.
3. Start something new in your life. To let go of someone you love, do something different in your social, professional, personal, or spiritual life. Volunteer, take a vacation, join a new gym, take a night class, join a support group, quit your job, find ways to take risks every day. If you're can't summon the strength or energy, you may still need to process your loss and heal.
4. Remember both the good and the bad parts of the relationship. When you've lost someone you love, it's easy to just focus on the great parts of your relationship and his or her personality. But, don't forget the flaws in the relationship! Remembering both what you loved and what you hated will help you say goodbye and move on.
5. Get professional help if you can't handle the breakup alone. Talking through your problems with an objective counselor, pastor, or psychologist can help you let go of someone you love by helping you recognize the big picture -- especially if you're scared or depressed. If you feel lost and helpless because he said he doesn't love you anymore, seek help. Support groups and strong, healthy girlfriends can also help you let go of love.