Avoiding catching colds? Tips wanted

this ^

plus i get this infuriating gravity-related sinus/nasal passage thing that stops me sleeping. basically if i'm anything less than 100% tip-top shape, evey time i lie down my left nostril seals shut like an airlock. the remaining one can't intake sufficient air to maintain restful sleep so i end up whistling, wheezing, mouth-breathing and and waking up evey 10 minutes with mouth like sandpaper and a headache. it's really very annoying. i haven't slept properly since last thursday.

Fuck me. Just found this. 6th September i posted that andI have had one cold after another since. Just near constant illness for nearly 4 months. I've never known anything like it. Think I should see a doctor?

Just felt on the 24th like I'd finally got over the last and maybe third or fourth consecutive cold that had lasted the last 3 weeks... Then the following day, christmas day, i woke up with yet another absolute streaming cold that is still going strong today. I am totally fucking sick of being sick. It ruined our anniversary dinner, both of our birthdays, I missed my work Christmas do and spend christmas day groaning, sneezing before giving up and going to bed. It' fucking embarrassing. Every time I see the in laws I'm fucking sick... Again. So so so fed up with it.