No need to worry - most here won't judge you especially in this forum. There could be many reasons why you feel this way and it might be a mix of several things. The simplest reason is, some people are Asexual and this means they don't feel the need to for intimate contact. This is the way they are and they're fine being like this. There's also some psychological conditions where they don't feel the need for sexual contact either.

Since you did at one time feel sexual desire, then you're probably not what I discussed in the above paragraph. If you're depressed or have suffered previous sexual abuse this could be the reason. Medications can also affect libido as well as not having a gentle partner. So as you can see there can be many reasons why you have lack of sexual desire. Do you have a doctor or therapist you can discuss this with? Its also important to have a patient partner who takes him time rather than just fulfilling his needs - foreplay is important. Would you feel comfortable sharing what you mean here...if not that's okay: