It can be platonic, familial, romantic, anything.
I’ll start: I recently moved in with my boyfriend, who lives with his wife and their son. They were already separated when we met, but his wife doesn’t want to divorce or move out, and she wants their son to live with both of them. My boyfriend agreed to those terms.
So now I’ve found myself in a pretty unusual situation…
Honestly I’ve always found it to be easier for me. Not to say many don’t find it more difficult, but I found monogamy to be stressful and nonmonogamy to generally just be a logistics problem rather than an emotions one.
Different people struggle with different things though