Dare to trust. Yes, people will take advantage of you now and then. Sometimes they'll even break your heart. When bad things like that happen, look for the lesson in the pain. But don't go through life as a cynic, or you'll never really live.
Bitterness is a heavy load that gains weight with time.
Forgive even when the pieces are too broken and scattered to put together again and you have to move on. And remember to forgive yourself, too. Be aware that even good people aren't perfect. Then read Suggestion Number 4 again. Don't limit yourself to small dreams.