You shy away from making decisions about relationships, because you think you've shown bad judgment in the past. But everyone has made mistakes; everyone has gotten involved with people who weren't good for them, or stayed in relationships that were ultimately going nowhere. True, maybe you've done this a bit more often than the average person.
But that's no reason not to try to learn from your mistakes now, so that you can create a better future for yourself. Part of your trouble with relationships is that you have a hard time seeing other people for what they are. You misread them and their intentions, and even when things start to come clear to you, you still might not make a move to stand up for yourself, take the relationship to the next level or move on. You tend to leave those decisions up to your partner, while you just follow along behind them. So why not change things now? If you can let go of your past regrets and decide to take a more active hand in your own love life, you'll be glad later that you did. Otherwise, you'll simply keep drifting along, never quite reaching your goals in love because you never quite define them.