My teeth are going to fall out

I really like candy, soda and other sweets and I eat and drink them a lot. I also have a tendency to forget to brush my teeth. This is bad because it can and has caused major effects to my teeth. I have had three cavities in the past two years, two of which occurred simultaneously last summer. I have also been told during my last two visits to the dentist that I had gingivitis, although the last time I went it was less serious. I've been trying to remember to brush my teeth and rinse with mouthwash but I just don't do it most days. And today I ate some candy, and also drank most of a 1-liter bottle of soda. I did brush my teeth this evening, though. So I'm treating this situation like I want my teeth to fall out, but I don't want that to happen, so I need to get better with my dental hygiene.