None of these things are true. With a good diet and exercise, you will feel better and be happier, with way more energy. That makes your life better, not worse.
As another commenter mentioned, abstaining from sweets increases your sensitivity to sweetness. If you go long enough, you'll find most candy cloying rather than addictive. So throw away those cheap, mass market candy bars. By some expensive dark chocolate candy from a reputable chocolatier. Eat one piece instead of a whole bunch and just take your time to enjoy the flavours. It is sooooo much better!
The way I see people (including myself at times) eat candy bars and potato chips bears more resemblance to a starving dog than a human who really enjoys good food. Stop being a dog! Take your time and enjoy something really good instead of swallowing a whole bunch of junk in front of Netflix.