In Hot Water

I have two, count 'em, TWO hot water bottles.  I think I bought one for myself, and then was given the other by either my mother or by my best friend.  I think the second one came with a fleece cover, long since gone (I hope).  I do kind of think my friend gave it to me.  I have a vague memory that I introduced her to the relief to be found in a hot water bottle, but she liked this other kind because it has a thicker construction, and for the fleece cover.  The thing is, that's exactly why I don't like it - to me, it doesn't transfer heat well enough or long enough.
It's not like I use one regularly, anyway - I won't use it during the summer, when it it hot, and during the winter, I don't want to stand around freezing trying to fill it with hot water, which I then need to dry off the bottle.  I'll try to use pain relievers first - the water bottle is awkward when I need it most, when I'm trying to sleep.
Going forward, how often will I need the thing?  I should be hitting menopause before the one I do use wears out.