I struggle most with getting motivated to actually do the things I enjoy.

Maybe you could try looking at your old interests in new ways? Like if you used to like pop music, maybe you could try jazz, or opera, or speed metal, or playing an instrument. If you used to like to read fiction, maybe now you could try reading biographies, or plays. If you used to like science, maybe you could pick a particular branch to study, and apply it to a hobby, like astronomy or botany.