i was thinking same as slimmer..this happens as we get older...and i believe you mentioned carrying a lot of weight around for some years...
yes, a good bed can help....i too would get a memory foam or therapeutic bed if could..
i also have chronic low back issues and i was recently addicted (2 years) to tramadol which i still consider a wonderdrug FOR ME...but very addicting as most pain killers...withdrawl was not as intense as what i read but instead took a week to get over the physical withdrawl (electric feeling in my back/restless legs)...but when i was on it helped with the joint issues as well...
last 2-4 months i've used sparingly aspirin and ibuprofen and even that is rare...
sleep is off and on....cant really pin it down to one thing....but i lean to the fact that MOST OF THE TIME its due to not doin enough during the day