I still bedshare with my 21m old. We've done this since he was about 2 weeks old, I was so exhausted I fell asleep lying down feeding him (followed safe seven guidelines without realising/by instinct) and it worked so well that I looked into it more and read up on the guidelines. it has been amazing, he feeds to sleep in no time, loves bedtime, we have loads of snuggly cuddles. my husband has slept in another bed all of this time and although I miss sleeping next to him, I wouldnt say it affects our relationship particularly negatively. maybe its even positive, we might keep separate rooms for good 😂
when DS was about 4m we put the mattress on the floor. when he was about 12m, we got him a king size mattress for a floorbed in his own room and we moved in there. I used to stay with him from bedtime onwards as DH has early nights so I don't miss out on time with him anyway, but now I get back up and potter round for a few hours.
bedtimes and nighttime have always been really relaxed. yes there's been hard times during regressions or illness, but bedsharing makes it easier than it might otherwise have been but overall its been good. we've never had to settle a screaming baby, try to put him down over and over, drive around for ages to get him to sleep, etc. just lay down, boob out, off he goes to sleep.