hi gresham, sorry to hear you are having such a rough time
if you are interested i can tell you which nutrition levels are poor in ms patients, and you can ask for some bloodwork to see if you need to adjust your diet and/or get a supplement regimen in place.
re the low b12 and iron, are you taking supplements to address these problems? do you have a serum ferritin result?
re your joint pain, have you ever had your vitamin d3 level tested?
re stiffness, aches, RLS, PCOD, headaches, and fatigue.. for me these all raise a red flag on your magnesium status. has anyone ever tested your serum magnesium level? can you get that test done? having better magnesium status may even help reduce your problems with recurrent UTIs.
also re constant UTIs, have you tried using probiotics? and/or antiviral/antibacterial supplements like zinc and selenium? i used to get recurrent UTIs too, but not since i got off the abx and onto some decent probiotics and nutrients. it is such a relief.
the forgetful thing i can also relate to - i was an absolute moron about 4 years ago (eg couldn't keep track of conversation topics, couldn't remember if i locked the door, couldn't remember what show i was watching when the ads were on, almost lost my driver's license due to really poor cognitive function, etc etc) but then i asked for a zinc test, was deficient (long vegan history), fixed it, and got better. it's awesome. i also worked a fish oil supplement into my regimen and i think that helps too. before i realized the zinc problem, at one point i used gingko biloba to increase blood flow (with the intention of increasing oxygen and nutrient levels to cells), and it made me REALLY SMART i highly recommend it for a short term quick fix! but you would need to keep working on the underlying nutrient status - your body doesn't use herbs for basic biochemistry right..
anyway hope you find something to help sort you out! if you are interested in taking on the nutrition approach, there are some links in my signature below (ie not the ones i wrote but please feel free to read those too) that i have found to be helpful resources.