Motivation is most often lacking in my own life. When I do experience it it is generally a side effect of an upswing in emotion approaching Hypo/mania. It will go hand in hand with irritability - not a nice mix.

I am inclined to blame the medications. i am very unhappy with that but I realise it is the cost of relative stability.

Do you find this gets worse during the dark and cold winter months?

Perhaps start with small tasks - like journalling every day. Yep it's awfully hard to get motivated to do so but in my own case it took about 4wks to fall into the routine. And I try to also do some art. Again, I just didn't have the where with all at first. Both are far easier. They are great exercises for being more motivated.

Something that might help is to sechedule yourself activities. I admit I am still lousy when it comes to being spontaneous. Planning activities ahead however seems to be easier.