OH,lifeinva13, I know your pain, I was/am in somewhat of the same place, married to a marine for 13 yrs to find out he was cheating during deployments while I stayed home and supported him and never strayed.My life was shattered.. but here is the thing about looking for support from the USMC...unless you can prove by photo or your husband admits to having sex with this woman no action will be taken. Here is the other thing ... they are sent on deployment with [censored] and condoms and with the line of.. "what happens on deployment stayes on deployment"
If you would like to talk more you cam pm me. I will be happy to help and support......