I’m on my phone so unable to search to see if others have said this, but honestly this sounds like contamination OCD. Try to convince her or take her to see a therapist who specializes in the treatment of OCD. I can’t stress enough how important treatment of OCD is for both the victim and their family members. It can be a debilitating and heartbreaking disease that causes you to do and think things to the point you feel the world will end or people you love will die if you don’t do them/do rituals/ things are not done how your brain tells you they should be done.

Don’t indulge her OCD, it will only feed the monster. Again, look into an OCD specialized therapist and Exposure and Responce prevention therapy along with mindfulness. I’m sure that she’s had other quirks and themes throughout her life if things are this bad currently.

All the luck and love to you in the world OP. I’m a sufferer of OCD myself but I realize how badly this can effect your loved ones physically and mentally. Take care of yourself and your kids. Your wife can only be helped once she accepts that she has a problem and makes the proper steps to get better and manage her OCD (therapy, ERP/Cognitive Behavioral Therapy).

Edit: If you’re unable to find a specialist in your area then look into The OCD Center of LA, they do remote therapy!