Stuck Between A Rock And A Hard Place

I am 18 years old and i am a closested bi-sexual. When i was 15 my best friend, who i had feelings for, slept over at my house. We were always very close but this night we ended up kissing, it was weird and very awkward but as the weeks went by we ended up kissing nearly everytime we were alone. A couple of weeks after our first kiss i asked her what she wanted us to be and she told me that she wanted to try and see if we could work. 3 years later we're still together but we've only told one person about us and now the obstacle seems to be the fact we're going to different uni's next year and i don't know how well a closeted relationship would last. I am in love with her and she is in love with me and i truly believe that we could spend the rest of our lives together. But theres just this huge shadow hanging over us and i dont think i can keep it a secret and still remain sane for much longer! I honestly don't know where to go from her.

I guess the real question is, is love always enough?