Reading fashion blogs has helped me a lot. I’ve been reading about capsule wardrobes and “effortless French style” (don’t make fun of me) both of which should be taken with a large grain of salt, but it has helped me to combine my current clothing in new ways and figure out which one or two new clothing items will fill key wardrobe gaps that I didn’t know were there. If you could get one nice simple black or gray dress, you’d probably be set for all the events you mentioned. Throw on a different scarf, cardigan, jacket, or jewelry to change it up. I’m a scarf girl myself. You can do so much with a scarf.