Love is wonderful because you get to be with the people you care about, are attracted to, and like. There are so many things that you can look forward to happening and doing together with your significant other when you're in love. Plus you just get that giddy feeling that makes the world shine a little bit brighter.
What makes it hurt is the disappointment we feel when we're in love. Our expectations may fall short and we find ourselves feeling disappointed, jealous, and/or betrayed. You have so much to commit to and you have to think outside of yourself which may be difficult for others.