If things are chugging along without conflict, the kids are not witness to fighting and abuse, then frankly its none of their business if you have an intimate relationship with your wife or not. You go on family holidays, presumably are pleasant to one another -really do you think your kids care if you sleep in the same bedroom? They are more likely to think 'oh gross' TMI! Seriously if they are doing well at school, have friends, do things like 'normal' teenagers they do not need to know the intimate details of their parents lives. Guess what? By the time you get to having teenagers, the idea of mum and dad holding hands or canoodling while watching the TV is gone...lol! You are probably not much different from their friends parents, except maybe they try and have hot dates when the lids are staying over somewhere. Answer questions honestly if they are asked but apart from that leave things be.