A couple of things. Don't underestimate what you H can do on the computer. My H IS NOT computer savvy, but the guys he works with helped guide him to AFF (adultfriendfinder.com). Also, you don't need a webcam to view someone else's. It's at least a plust that he does view it in front of you....so that right there, tells you his "I don't think about sex." is absolute bunk.
I REALLY recommend finding a good therapist, someone who will see you both together, and individually. Someone who specializes in marital issues specifically. Call around, if you have insurance that covers counseling ask them for a list of recommendations. Then phone several of the people on the list and ask for a phone interview (that's how I selected the therapist who DID end up helping us the most.) Let him/her know you DON'T want to D and that you are wanting to avoid that, and give him/her a brief accounting of the sitch. The responses you receive will IMPO tell you who to go with. Many therapists never called me back, some would simply refuse to speak to me for a few minutes. The one who actually called me back and gave me some time on the phone is the one we went with. She obviously cared and wanted to help.