I logged in just to help ! I found the issue, you can only “suggest match” with single sims !!! Hope this helps !!
Hello, so I tested without mods! The interaction shows up now, so I'll have to go through and figure out which mod causes the problem. Weird that I did get the interaction available once when I had mods in, so kind of an odd problem since it wasn't completely gone from the game. But I also realized I can't suggest a match to a sim in my household. Not sure if that's on purpose or not, or if it could be a suggestion to EA to add that. I had my sim's single sister in the household, open to relationships, full friendship--but no option to suggest a match. Then I removed her and it immediately showed up. Added her back, and the option disappeared again.
And also can't with any sims in a relationship, even just dating, not only married. And that's a good point, @simsplayer818 , that it might depend on their preferences about open relationships! That's fine for me gameplay-wise.
