Vitamin B6 does loads of things. (besides work with folate and B12)

What does it do? Just about everything:
http://www.dietandfitnesstoday.com/vitaminB6.php

Low B6 leads to low serotonin and hence low melatonin= poor sleeping.

People with low B6 may have pyroluria. This is a genetic error in producing heme (for hemoglobin). The byproducts of this heme production called pyrroles complex the B6 and rapidly dump it into the urine and it is lost.

Pyroluria also depletes zinc.
You can have a zinc/copper ratio blood test done to see if you are low in zinc also.
The definitive test for this is a urine one, as described here:
http://www.drkaslow.com/html/pyroluria.html

I have a thread here on B6:
http://neurotalk.psychcentral.com/thread30724.html

I suggest you use activated B6 instead of old pyridoxine. You may not be converting the pyridoxine in your food properly.
This is the one I use:
http://www.iherb.com/Now-Foods-P-5-P...blets/740?at=0
it is enteric coated for better absorption. One a day is usually'
enough, for most people.

B6 is depleted by:
Birth control pills/female hormones
most antibiotics used long term
most diuretics
INH (anti TB treatment)
hydralazine (for blood pressure)

Very low B6 levels cause peripheral neuropathies.

B6 is involved in carbohydrate metabolism, protein and fat metabolism. Without it you cannot repair yourself.

I'd get those zinc levels run as well. Low zinc causes poor immune response and poor tissue healing among other things.