I have that same problem, I'm on Klonopin as well. I can get off with masturbation, but not with my boyfriend. That might be some kind of mental thing but yes, I have noticed a change. SO maybe Klonopin has something to do with it.
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-DERANGEA
"All credibility, all good conscience, all evidence of truth come only from the senses."
I've been on again off again taking Klonopin (Clonazepam) and it did that that very same effect but after a short while, it subsided for the most part.