Welcome to the forum. Welcome to gardening. Yes, the first thing you will learn is that plants do get sick and die, and lots of critters and diseases get after your plants at times.
Rain and cold, not good for the plants. Usually they will survive though unless it freezes.
" I added 8-8-8 a week ago" Hmmmmm, be advised that too much fertilizer can kill plants. Always be careful adding fertilizers and follow the directions on the containers carefully.
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-