Call Every Ex You've Ever Had So you don't have a date for Valentine's Day. Big whoop. Just because you're sad and miserable on this romantic day doesn't mean you have to be the only one. Call all of your old girlfriends sometime in the early evening, preferably right before she is about to go on her hot, steamy date and inform each one that you still have feelings for her and that you are thinking about planning a trip to come see her. Remind her how great the times you had together were and that you're still really broken up over sodomizing her gerbil with toothpicks. After all, you were in a really weird place at that time in your life. Once she is thoroughly perplexed and angered, hurl an extremely vicious insult at her and hang up. Date ruined, mission accomplished.
Harass Couples on a Date Drive around for a while and try to spot a couple in a car. Tailgate, honk, flash your brights; do whatever you can to put the man in the awkward spot of either going into a violent rage or seeming like a raging pussy. Either way he's shit outta luck and his ladyfriend will reconsider why she's with him in the first place. Then she'll remember that he's loaded. Fuckin golddigger.
Go to Dinner Alone and have an accomplice inform you that your date died on her way to dinner. Make a big scene and go table to table lamenting the loss of your one true love. For an added bonus, show people the engagement ring you were planning on giving to her.
Shoot People Like, seriously, a lot of people. Shoot them dead. That'll show them to be happy.