Apologies in advance - this is long 
My DH has contamination OCD. His focus is asbestos. Long story short, our shed roof is made of asbestos and sustained minor damage by a contractor (who was made aware it was asbestos before hand, but wasn't very careful). The situation has been assessed by professionals, who said the stuff in the shed will need to be decontaminated, but the decontamination work DH did outside the shed would be sufficient. Two different professionals have said there's no way we will have any negative health impacts from anything outside the shed.
DH has always had a touch of OCD, but covid made it MUCH worse. He insisted all shopping was washed before being put away, refused to go into any shops for over a year, and if someone so much as placed post on the side everything would need disinfecting.
We're both now double-jabbed, so he's actually not too worried about covid now, but around the same time the above incident occurred and he transferred all his OCD attention onto that instead. None of us are allowed in the garden, including the dog who has to be walked down the road for a wee. I'm not supposed to take my toddler to see her elderly and lonely grandmother (next door, DH's mum) because he knows she went out in the garden and doesn't think she would have washed her hands properly. To do the bins, I have to wash my shoes after going out the back and also have a shower. He spends literally hours cleaning things obsessively if he thinks any kind of contamination has occurred. If I accidentally brush past some washing hanging to dry then it has to be rewashed.
The worst bit is that it's affecting our almost-2-yo DD. DH considers work his safe space, so every morning he has a shower then can't touch anything (like, I have to let him out of the stair gate etc.). I have to drive him to work because the car is considered "dirty" apart from the passenger seat which he spends hours cleaning. From the time he comes down to the time we leave, he panics if DD tries to come near him.
He will actively step back away from her, which is sad when she just wants to say hi to daddy. I'II literally have to plop her on the sofa with my phone so she doesn't run round. When he gets home he immediately changes his clothes and then he is ok to play with DD as he just accepts he is "dirty".
He knows it doesn't make any sense, and knows logically there is no harm. We had the house tested for asbestos, which came back negative, but he can't relax as of course the lady didn't sample every single surface.
I'm not allowed to use certain areas of the house which he considers more contaminated. We were/are in the middle of a long renovation before all this happened so literally stuff everywhere that I want to get cleared up but not allowed. If I accidentally do touch a contaminated area he says it feels like I am torturing him and accuses me of not helping him, even though I literally do so many weird things in a day to try and make him feel safer.
I was reading recently that my approach to try and help him is actually doing more harm than good, and that really family members should not be helping in cleaning rituals etc. So that made me feel shit. He literally breaks down if he thinks there has been a contamination event and gets very upset. He also gets very frustrated if I suggest things don't make sense.
He saw a Dr a month ago after eventually accepting this isn't normal, and he's now on citlopram. He is awaiting therapy, but has been told the initial consultation may still be another month or more away. I don't know if I've fully got this across well, but the situation is all consuming and heartbreaking. He can't think about anything else. No work on the renovation, no plans for the future, and until a couple of weeks ago he was spending all weekend cleaning things rather than spending time as a family. I guess I should be grateful for that improvement, but I am struggling to cope with the constant stress. I think about leaving, but that feels awful as he's a great dad and husband when he's having a good day. I just wish he could get better soon.
I'm not even sure what I'm posting for - just feel so alone. If anyone knows of any family support resources/groups, please do let me know.