What if you said "I am not someone who will stay in a sexless marriage.". I know it's still just semantics but I think if it is phrased that way it conveys even more acceptance of the partner's right to remain non-sexual. How about "I am a person who values sex too highly to remain in a sexless marriage."
"Tell me, what is it you plan to do with your one wild and precious life?" - Mary Oliver
