Needing encouragement...(semi-long)

CPA04

Backstory:  STBXH wants to take B tomorrow to go out with his parents.  I said no, but that I have no problem with them coming here to see B (in reality it makes me incredible uncomfortable).  STBXH gets angry, verbally abusive per the usual, and then STBX-MIL calls and repeats the process.  I'm an awful person, B will grow up and despise me for "keeping" his family from him, that STBXH's affair is something that "just happens" and that's society, it happens to lots of people. That the fact STBXH relapsed last month should just be forgotten about.  And that none of their other friends who've gotten divorced handle their arrangement like this so I must just be out to get him.

We have mediation on Wednesday and I'm asking for supervised visitation for STBXH because of his track record and because that's what the child psychologists have recommended given our situation.  There is no way I could propose that and just hand B off to them tomorrow.  It isn't right....right?

Am I doing the right thing here?  It sucks that there are so many people who think I'm a horrible person for the way I'm handling this situation because they're only hearing his distorted/delusional side.  It's getting to me and it hurts.  I'm just trying to do right by B, be his advocate, and it seems like everyone else is just putting STBXH before B.

Thanks for listening.

ETA: I think they need to see that I have to take these measures because of the choices STBXH has made and due to that, they should be angry with him, not me.  But then again, that would be rational wouldn't it? It's much easier to blame anyone but him for the situation he's in.  The addict is always the victim right?....