I'd have to ask myself why I needed spaces from someone that I love and want to spend every waking moment with.
I think that's the difference. I do NOT want to spend every waking moment with my partners. Just like I'd like to be alone when I use the bathroom, for instance, there are other times when I feel the need to be alone and focus on myself without outside "signals" or distractions.
I feel it's good to have quality time with each person individually, one on one time to spend together and give 100% of your attention to that specific partner. And similarly, I feel the same need for myself.
I guess it goes along with the idea that you are your own primary, to me.
Own space to retreat to? If you share a room with your partner, is this not considered yours space when they are not in it?
I feel it's different. The thing with a "safe place" or a "retreat" is that you know nobody will barge in and interrupt you or disrupt your solo time. If it's YOUR room, people need to ask for permission, or even know they can't ask (for instance, if you have a policy that a closed door means "do not disturb").
You can't do that in a shared space, because people would be locked out of a place that is also theirs and that they might need. It would be bad for them, and bad for you, because you'd constantly stress out that other people might need the room, and therefore not allow yourself to spend your quality time for fear of bothering theirs.
It's a bit like sharing, say, a piece of clothing. Every time you wear it, it means other people you're sharing it with can't. If you all need it at the same time, it can be a problem. Might as well all get your own.
I think it really comes down to the people's personality. Maybe you don't need any alone time. Maybe you hate any second you are alone. I've known people like that, who have never lived alone, always had a roommate of some sort because they can't stand the idea of living alone (and not for money reasons).
And then you have people who, as much as they love other people, also require alone time. I am like that, and it takes a great deal of solitude before I feel lonely. I can spend days not seeing another human and not realise it. (Well, that hasn't happened in a while now, since I'm married and live with my husband, but it's not something I have suffered from in the past.)
To become someone I'm comfortable around takes a great deal of time and trust, and even then it will never be a 100% of the time kind of thing. And certainly not 100% of the time with two people at once (or more).
Each person reaches a saturation level at some point, and I need my alone time on top of that. I don't think it means I don't love them, just that I work differently.
I have just come from a situation where I had no place to call my own. I love being all in the same bed, I love that everyone helps out with child care, supper, gardening etc. There is nothing I love more than all cuddling up together, going for a walk together, sleeping together, playing together... but I require a place to retreat to. Something to regain my inner self. I didn't have that before and I think it's important that everyone have that if it is what they desire.
