Hey C.,
Gosh, I am so sorry to hear your plight! I SOOOOO know what you are going through. My oldest son, who is now 12 thank god!!, was born in December and was on a nebulizer by the time he was 2 or 3 months old. He was so congested and snotty all the time that I could never get it all out. Even with those ridiculous little snot sucker things. HE HATED THOSE!
Eventually I discovered on my own that he just had seasonal allergies, but they were all seasons, lol! He is still very snotty and all that most of the time and he is usually needing to blow his nose just because he has a more than normal amount of mucus and whatnot up there that if left alone without regular nose blows and allergy sinus meds he can be a really gross mess.
See what your doctor can prescribe you that is like Mucinex for little kids or I think they make that for little kids now, IT IS SO GOOD, better than even most prescription strength things I think and that will help break up the congestion. The biggest problem you are having is that he is not getting all of it out and it is just sitting there in his body making him sicker. Your body is supposed to do that kind of thing as a defense mechanism, however, when they are little like that they can't get it all out on their own, i.e., nose blowing and coughing it out and spitting out what accumulates in their chest and what not, that is why it has gotten so bad. He needs an expectorant to help him get it up and the decongestant to break it up. So once it's broken up good, the expectorant will help him to expectorate or "get it up and out". Once you get all the old yuckies out his condition will probably improve dramatically.
After he is finally well, keep some kids strength allergy sinus stuff around and about a week or so before the actual change of the seasons on the calendar, keep it handy, because that is the key to keeping him well. If at the FIRST sign of a sniffle or a cough, watery eyes or what ever that symptom is for allergies, give him the allergy sinus. It will help stave off the yuckies before they get started. I know this situation has been really hard on you and him as well. But trust me, from what you are saying, that is kind of what it sounds like to me.
Thankfully the older he gets, the easier it will get for YOU. He has to be able to cough it out/up and blow his nose on his own to get rid of all of it. My son is now like I said, sniffy most of the year, but if he takes his allergy sinus stuff he usually just ends up with monstrous boogers, lol!
I hope that helps you out a bit. God bless you and your family and I wish you MOST LUCK with this as I know it is not only a worry for you but is also VERY ANNOYING!! You just feel helpless and like snot is gonna get your kid, cause really that is what it is.
Take care,
Kat