Thanks for the tip and the suggestion. I will try stop self-pleasuring and see how it goes.
Hi. I had your same situation for quite some time. How I resolved it is thru my own experience and opinion....
On 9-17-10, I stopped self-pleasuring myself. I believe the way I masturbated thru out the years, I desensitize my penis head (rubbing the penis head directly with vigorous rubbing). Just like you, I'm sometimes okay during unprotected sex but stood no chance with a condom on.
On 9-17-10, I also started wearing the manhood, something I disover over the net thru research. You can see and read about this @ manhood.mb.ca
Conclusion: After 30 days of no self-pleasure and wearing my manhood, I feel the increase in penis head sensitivity and feel stronger erections. I had sex with a latex condom 3 different occasions and manage to feel pleasure and reach ejaculation.
As of now, I don't know if it's no-masturbation, wearing the manhood, or combination has helped me to gain back sensitivity. So I continue to do both methods.