I really think that how you feel about time apart depends on the dynamics of the relationship and you and your partners personalities, not how long you have been dating/married or how "mature" your relationship is.
Also, some people marry because they love the person, and they are friends, but not crazy in love. I know many couples that are more companions than soulmates, and if it works for them, that is fine.
I would never judge someone else's relationship because everyone is happy from different things.
Some people never stop being crazy in love. Some people never were crazy in love from the first place. Some people go in and out of it.
With him being a police officer, I never know when our last day together may be, so I treat every day as if it were the last and love to my fullest.