How to Handle a Jealous Husband?

My husband and I have been married for several years and have been together since high school, so over 10+ years.
We have 2 kids together. He is extremely jealous and posessive.  He is constantly bringing up ex-boyfriends, male co-workers and male friends and accusing me of having an affair with all of them.  I have never cheated on him before nor do I plan on it. I just wish he would stop with the accusations.  Everything is related to sex or a sexual relaitonship with him. If I get a promotion on the job he assumes I slept with the boss to get it.  If I acquire a new client or business partner he assumes I acquired him/her through sex.
My question is; How do I handle him?  I've tried asking him what makes him so jealous and I get no answer. I'm tired of always defending myself, especially for things that I'm not doing or have never done. It's a constant argument between us. I think he has a personality disorder.

[Roger Gould, M.D.]

Most often the common sense explanation turns out to be correct. Your husband is insecure about himself and worries he is not man enough to deserve or hold you. There may be other explanations why he oversexualizes this insecurity.  the best way to handle this would be with a therapist who sees couples and help you explore this together, and help your husband at thesame time...You may be able to accomplish this in just 3 or 4 sessions.

[RkMishra]

Sir,
In the above case, is OCD is associated in any way ? Since the concerned Husband in the above case has a repeated thought of alleged indulgence of her wife with others.He can not throw this thought out of his mind. --Or-- if it is the symptom of some other mental illness ? If so, whether it can lead to an OCD in future ?
In one case I have seen that same thought of doubt was prevailing in the mind of a newly married person for 1-2 years and afterward he suffered from OCD associated with CLEANINGNESS (Fear of contamination from cloth/water and other objects touched by some other persons).