Hellooooooooo
I have always co-slept, just find it easier with breast feeding, and if it means I get more sleep, I would do anything! My sister however put her DS in his own cot in his own room from day 2, she said he 'snuffled' LOL I do agree about the regulating breathing thing.
It is totally different when you are looking at your baby, I couldn't have put either of mine down, walked out and shut the door, and left them there, call me a wuss or whatever you like, but I couldn't do it!
We had/have a playpen down stairs, that has a multi-positional base, so when DS2 was tiny, if he slept down stairs it was in there, and then obviously as he grew the base could be lowered, now he only goes in it to play, but we did find it invaluable when he was little. He also had a swing and a bouncy chair that he'd sleep in down here.
Then up stairs, we did have the travel cot (that had a basinet level, was this one) in our room, and he spent a bit of time asleep in there, but mostly if we were upstairs he was in with us.
BB, we have a cat, she does go out but is mostly found curled up in a ball somewhere near the raditors or fire... She was fine TBH. We obviously never left her and DS2 alone in the room together, and she doesn't go upstairs anyway. She did used to like to have a sniff of him, but she lost interest, until he leanered how to stroke her, now she comes in and goes straight to him! And he will now say cat and that tut tut tut tut sound that everyone seems to do at cats!
We got into town, DS1 decided his trainers were hurting, so I had a feel round them and they were a bit small, so had to go and get him new trainers, then we walked past Adams and they had 'Buy two tops get thrid free' so thought I'd have a nosy, came out with 5 pairs of trousers/jeans for DS1 and no tops, typical, he isn't even that bad for trousers, it is tops he needs! So £100 down the line, and I hadn't even got anything I actually went in for by then! You lot wanting kids.... don't do it!!!!