I can't really offer much advice with the family dynamic, but I can share my experience with a septoplasty.

I've had a septoplasty. It would take me 2-3x as long to clear a cold than everyone else and I'd come down with at least one sinus infection every year until I had the surgery. By the sound of it, if your ENT (Ear-Nose-Throat specialist) has recommended one for your symptoms, it is worth doing. It has made a big difference to my quality of life.

You can explain to your ENT that you're nervous about the surgery. In my case (because I am terrible with getting an IV/drip for anathesia) they used nitrous oxide to knock me out so they could get the IV in for the surgery. Last thing I remember was breathing it in; then nothing else until I woke up in recovery. If you've had past surgeries involving anathesia where you've unexpectedly woken up, make sure you tell the ENT and anathetist beforehand so they can take appropriate action. If you've had no problems, though, you can remind yourself of this to help reassure yourself that you'll get through the surgery fine.

If you're used to constant congestion and other nasal issues, then most of the post-surgery period is not going to be any worse. It's really only the first 2-3 days that are particularly uncomfortable with the inflammation, mucus and post-surgery bleeding (there shouldn't be any significant bleeding after the first night, especially if you follow your ENT's post-surgery advice - usually regular nasal/sinus rinses which helps flush out the mucus and muck). Even then it's still possible to get some sleep; you're unlikely to be falling asleep randomly the next day but will feel pretty tired and sore. Plan to have a slow couple of days relaxing (e.g. watching TV or reading), and allow for the possibility of taking a nap in the afternoons, just in case you need it. That way you have more control over where you sleep if you need to.