Bad Breath for 7 Years?

by Jack
(Maldives)

1- Five years back, one day I had a cold chocolate drink, and my upper inside gum in the middle at the base froze and stayed that way for a few days. The doc said my upper 2 front teeth were too thin, so he fixed them.
2- 3-4 hrs after brushing, I started to feel not brushed, salivary, sticky and bitter taste on my tongue.
3- Later, when I eat hot food, my upper gum started to swallow. My teeth became sensitive to hot or even ice water.
4- At the base of my lower teeth started to break away.
5- I brush very often. My teeth are white. I use mouthwash of all kinds.
6- Spicy foods make the inside of my chest to a burning feeling
7- 6-7 yrs back, for two years I used to take Brufen (Ibuprofen) tablets for a pain to get strength to play sports. Then I stopped and never take them again. I smoke 20 a day and eat Areca nut regularly.
8- All this happened without my knowledge that I have bad breath. It's not natural, and it wasn't there before, and it's there now. No doc showed a solution so far
WHY?