Zoloft or any other kind of ssri antidepressant will cause inhibited ejaculation. Diabetes can cause the penis to lose sensitivity due to blood flow problems and nerve damage. But, ejaculatory difficulties caused by diabetes most times take years to occur. I would guess your problem is being caused by the zoloft.

Ask you doctor to try a combination therapy to treat your depression. The antidepressant wellbutrin will not cause sexual side effects. Perhaps if you cut your daily dose of zoloft in half and also take a dose of wellbutrin, the wellbutrin will cancel out the ejaculation problem. You might also consider taking viagra before sex. Even if you don't have erection problems the viagra will increase blood flow to the penis and make the penis more sensitive to stimulation.

If the half and half dosages of zoloft and wellbutrin don't solve the problem talk to your doctor about slowly, over the course of a couple of weeks, cutting down the dose of zoloft more and more and increasing the dose of wellbutrin. Do this until you no longer have to take the zoloft. This must be done under your doctor's supervision so he can monitor the effects of this gradual change of meds.