Normally, men in middle age report being hard pressed to ejaculate even once per day, on a daily basis. Adolescent reported ability to masturbate until ejaculation six, or more times per day. However, it is apparent that the ability to masturbate declines with age. Your husband will enjoy doing this until he can reach erection no matter what you say. Well, simply to say, you cannot run away. You are probably not interested into techniques of masturbating, because you want to run away from this. You need to know there are some techniques, which may work for one can often be quite painful for the other. Although techniques may also differ between circumcised and uncircumcised males, I can tell you that your husband enjoy doing this. I would like to tell you masturbating are nothing bad, and you should not think as you do.
I have to tell you I am younger then your husband, but my 37 years are also important in answer, as you want.