Hi.
It's hard to place a standard rating on how important physical attraction is in relationships because its importance varies from person to person and situation to situation.
There are many ingredients that go into relationships, including shared interests, emotional compatibility, and social aspects, like how well your boyfriend gets along with your friends and parents; physical attraction is a part of this mix.
Sometimes people find that the other parts of this mix, taken together, make up for a weak physical attraction, but it doesn't sound like this is the case with you and your boyfriend. It sounds like you would prefer a platonic friendship.
If that is the case, it might be best--for both of you--if you were to tell him the truth. Since you really do like his friendship, you might want to emphasize how much you like spending time with him and let him know that you'd like to resume a friendship with him when and if he's ready.
He may need some time to adjust to the idea, which means not spending time with you at first, but he may eventually come to accept this idea. Or he may find it too painful to be around you if he continues to have feelings for you. That is the risk you take by leveling with him.
However, think of the opportunity you will have to open up your life to new relationships and new people. Now that you know the kinds of traits to look for in a boyfriend, try to find someone who will also make your toes curl when you kiss.
Good luck.