Lower back pain, same pain for about 2 years? Some days are worse, others are better.

Lumbago. Sounds like you need an evaluation. The best advice would be to see a spine specialist. Most likely a good course of conservative non-operative measures will be recommended, unless severe pathology is identified as the source of pain.
Degenerative disease. Could be many things. Likely some type of degenerative problem. Recommend an evaluation & x rays.