Husband's semen analysis

 I need ur help badly, 

We've been TTC for almost 3 years with no luck.Its becoming emotionally draining. After a year of try i went to specialist.she checked me out now the 2nd step is getting him checked out. they gave us a kit so that my husband can have a semen analysis. He tried his best but unable to collect sample. He was not comfortable with masturbation ,so doc allowed us to '' do it at home '' and drop it off at clinic. I tried to comfort him and help him in all possible ways with no success. He feels so helpless he's been trying to collect his sample from last 2 year. I feel so sorry for us. We are having  a hard time for not been able to know what exactly the problem is. Please please help me. Without semen analysis we cannot start further treatment.