Is masturbation part of a healthy marriage?

Ok so there was an interesting post in the May 2019 Babies room earlier that got a little touchy for some. Basically, the pregnant poster said she caught her husband masturbating for the first time in their marriage, and was furious and shocked by it. Commenters then replied with some wildly varying views on the subject of private/solo masturbation as part of (or not part of) a committed relationship.

Personally I think that as long as communication lines are open and both partners are being honest with each other, there's no reason to treat a little "private time" 😂 as a threat to a normal, healthy, satisfying sex life. I think the two can coexist in the same relationship just fine.

Some of the commenters also expressed shock at having found out their husbands masturbate, and I couldn't help but wonder...do some women expect their husbands to stop after marriage and just do intercourse alone? Why does it bother them--insecurity, fear, or something else? And most importantly, do women who feel their husbands shouldn't masturbate also stop doing it themselves?

This is such a fascinating discussion to me and I'm genuinely curious what everyone thinks.