@garland I absolutely love that metaphor 
I think that all couples are going to be different, that some couples are very closely intertwined with most things, others can have very seperate interests but can otherwise have a fine marriage/relationship. One way I kind of visualize it is it doesnât matter what planets the people are one, some like being on the same one, some like being on different ones, some spend time on different planets but also on a common one, and what matters is that they are revolving around each other:).
Being empty nesters (our S is finishing his third year of school), it didnât really change things much, other than my spouse could sit back and smell the roses a lot more, literally and figuratively, without the day to day involvement with our son, being his head tutor, major domo, driver, etcâŠin many ways, we are where we were before he was born (we were together almost 10 years before we had him), we enjoy spending time together and sharing things, while we also do have seperate interests. There are frictions there, in some ways we both had what @oldfort talked about with her H, where we can be responsible for each otherâs happiness, there is still a lot of old crap from our pasts that kind of make that happen. The one big issue we have is that my job is both time consuming and stressfull, it is helping pay for my sonâs school (full freight) and such, but it also takes a toll. The hard part I think for us is developing some of our own interests, so much has been spent with the things we needed to do, it can be hard for us, for example, to spend money on a hobby or interest and I think that would help us.
I think with the problem with parallel lives is when everything is parallel, when the two people are living together and it is kind of like friends or room mates, where nothing is in common, even if the common thing is snuggling in bed, or talking about their own interests, or having dinner together, there has to be something, otherwise it is two planets in my metaphor that might be circling the same star, but not revolving around each other.
separated but cohabitating is very specific and really awkward, and the women I met while trying it, on our counselors advice didnât buy it. Wifey and I are making an effort to do some things together, like meet for dinner, a movie, a get away, etc. during the week we donât try to get home to eat dinner at the same time like we did when the kids were around. so yeah, we are leading somewhat separate lives but really itâs more about activities / errands and not about actually dating other ppl. we always settle down for the night together like with dessert & TV before bed, and we go to bed together, usually at the same time.