Sounds to me like you still have feelings for your previous girlfriend that goes beyond friendship... You say that you're like best friends and that you like her but that you are not sure if she likes you. I assume you mean if she likes you more than just a friend, right?
On the other hand, you have a current girlfriend that loves you.
Well buddy, you have to make a hard decision. You have to choose between your ex girlfriend and your current girlfriend. And, you know it. Which one? Go with your heart.