ellz I feel you, man. What you're describing is exactly why I always say growing weed is not easy at first. Or, should I say, growing mediocre weed is easy, but growing great weed takes practice and a lot of money. If I vape my own weed for the next 25 years, I may make back my investment...
Looking back over the past 4 years during which I've spent so much $$$ fine tuning my grow room, I would not say that growing weed is for everyone. In the beginning, the problems seem to come thick and fast as we learn ropes. I have a buddy who's on his second grow, and he has experienced all sorts of problems on both: light burn, nute burn, hot temperatures, root-bound plants that never bounced back, weak ass weed at harvest. I try to point out some things to him, but he has to learn on his own terms, I reckon. Just like I did: I had a terrible case of root rot on my second grow, but I took care of the problem ($$$$$) and it didn't return.
Starting year 5 I would say that it's getting better. I have everything on hand that I need to get rid of any problem I have in my grow room, including pest killers (I haven't had spider mites, but I've had fungus gnats.) But I LOVE GROWING WEED: it's the most fun I've ever had, it's a great hobby for me, and I love producing my own bud. I don't live in a legal state, and the shit that sells around here is absolutely pathetic. One guy was selling weed that he grew with moth balls in the shed to disguise the smell. That's the level of ignorance, danger to your health and carelessness around here.
I hope you can salvage some bud. The universe doesn't hate you, and I'm really sorry to hear that you feel that way. Life throws shit everyone's way: it's the nature of life. You can handle the shit and bounce back, Ellz. Have some faith in yourself!!!