My first husband stopped doing his duty not long into the marriage, I had affairs, discrete, no strings with plenty of scope for deniability.
My next partner I remained in a relationship with no sex after the first 18 months or so. We were together 19 years.
Due to botched surgery and other problems Dave and I couldn't. It affected him really badly and it was hard for him to believe he was still my man, and as his health deteriorated even mucky cuddles were less frequent then stopped altogether as it was increasingly uncomfortable. Never once did I think of straying, even DIY would have felt like a betrayal. I really believe it depends on the person you are with I didn't love my first husband I liked him a lot but in the end I had the wrong equipment so I wasnt giving away something he wanted anyway