I don't think there's an easy answer. Taking the wife/gf with you now and then might do the trick. I've been on site with a colleague who had to leave early because his significant other had stopped answering the phone. I guess it all depends on the none travelling partner; some are ok with it, some are not ok with while others try very hard to be ok with it while not actually being ok with it.

I have another colleague who perhaps only travels 2-3 times a year and he thinks the "me" time this gives both of them is good for the marriage. Any more time than this though and he's well and truly in the dog house back home.