We both love each other but can never be together....bitter sweet!?

I love my daughters mother still with all my heart, and yesterday she confessed to me once again that she still loves me too. We have a 2 year old baby together and we have had a 5 year relationship on and off, however, we always hurt each other. We have to much in common and we think a lot a like in many ways... thats why I believe we can't make it work. Pluse the make up the break up patterend has been to much on both ends. But yesterday when she confessed to me that she still loves me and misses me... it made me feel bitter sweet! It's like one of those movies you watch on TV were two people are very much in love but can never be together. It hurts very much and like I said its bitter sweet... how can I handle it and what can be done! Ladies please help me understand.