Born March 29 1993 I am a Rooster.. Seeking guidance on relationship.

I'm a girl who has guys for best friends. But one of them stands out from the res he's the year of the dog. He understands me better than any of them and we talk constantly even if either of us are in a relationship. I don't want to ruin or friendship because I love him so much. I want to get closer to him but I don't know how. What should I do?