I have been where you are...ugh. I know how it feels.
Here's what helped me:
1. Change your diet..elimate "whites" white flour, sugar, rice, dairy.
2. Colon cleansing - get the gunk out...you'll be AMAZED
3. Liver Cleansing - amazing for allery issues also.
4. Neti pot - I couldn't use one b/c I was too congested (complete blockage). If you can just get a little salt water up there on a regular basis though, you'll be amazed!
5. Practice deep breathing once you have cleared the way. Likely your body needs the oxygen if you've been stuffed up so long.
6. Alternate hot and cold shower - this is a QUICK fix that gave me good relief in a bind.