4Foxy11,
First off, sorry to hear about your breast cancer, keep fighting and stay strong!
As for your BF, has he ever done anything like this before? or is this just a new thing? If he has had this type of behavior before it could be there is an addiction. If this is a new thing, it could be nothing. As with any type of addiction, it is up to the person, if they want to get better. I know he isnt smoking crack or shooting dope, but a serious sexual addiction can be devistating to a family/relationship.
If he hasnt shown this type of a behavior before, it could just be that he might be a little bit alone sexually. Given your situation, this is by no means your fault. Having seen my father go thru chemo, i know how hard it can be and energy comes at a premium. My hopes are that after you are thru with your treatments and you get your strength back, you guys with both be able to show each other how much you've missed one another.
As for him ending those relationships, its quite simple. if they are people he has known from the past, odds are they know your guys situation. All he has to say is that its not fair to you, to have these types of conversations and leave it at that. If they want to be there for him as a support system thats great. But he needs to set a clear boundary. He seems like he is a good man, as you said he is there for you and is caring, etc.
But it never does hurt to talk so someone about these types of things and yes therapy does help. You just have to be willing to put it all out there and open yourself up...which for most men is not an easy thing to do, so if it is serious it could take time. As with any addiction there is an underlying issue, that drives that addiction. Once the addict figures that out, then they can begin to heal those wounds and move forward.
I wish you the best of luck in your battle, stay strong, there are millions of survivors out there cheering for you!
Best of luck with your BF hopefully you two can get this straightened out!
IC