Frustrated!

I am in an open marriage to the most wonderful man in the world.  We've been through so much together and are stronger and more in love than ever.  I am also in love with another man.  The other man is in love with me but won't let himself go because of the fact that I am married, and he either wants me all to himself, or not at all.  I can understand that but its still very frustrating.  We have talked about it and after having slept together twice, decided that our relationship should stay platonic.  Every time I talk to him or see him, all I feel is a sense of longing and being unsatisfied.  I just want to accept a platonic relationship with him without wanting anything more.  Logically, I would rather have him as a friend than not at all but I am still very much in love with him.  I wish I could just not love him anymore...