You said that you think that having been alone for 3 years is connected to your inability to have an orgasm, but you didn't mention what you think the connection may be. It sounded like you were also thinking that your inability to achieve an orgasm through masturbation is also related to the 3 years that you were alone.
You are going to need to flesh out this link in order to unravel the unconscious conflict that is blocking your sexuality. I wonder if you are saying that you are afraid to let go sexually, whether your are alone or with a partner.
Is holding back sexually a way of protecting yourself from loving fully. The more you love the more it hurts to lose. Could you be afraid of loving and losing and being alone again?
If this is true, then masturbating to orgasm could be seen as dangerous since it would open you up to wanting sex with a partner, which is risky. Free associate on what you think the link between being alone for so long and not being able to orgasm is.
If you can't make the link, you could try hypnosis, to see if you can reach that part of yourself when you are not fully conscious. Seek and ye shall find the answer.
Once you identify the underlying problem, you can take steps to heal it. If you are still stuck, we can do a private consultation in which we work together to unravel the mystery.