Factors that break wudhu

Wudhu and fasting for a person who has a problem with bleeding gums

Q: I have a problem of bleeding gums. The bleeding occurs anytime during the day or night. Sometimes I am unaware of it and other times I spit and rinse my mouth when I get taste in my mouth. My questions are 

1. How do I maintain wudu in this state? This is causing me to perform wudu multiple times sometimes. 

2. How do I fast? I try my best to rinse my mouth continuously when I am awake to avoid swallowing. But I am worried about when I am asleep and don't know if I swallowed or not. 

3. If my fasts are becoming invalid what is the kaffarah I need to pay? Should I pay for all the previous Ramadans because I am not sure about when I started suffering from the bleeding gums problem.

Making wudhu after eating food cooked on a fire

Q: There is this book called "The Tablespread Of the Holy Prophet" written by Muhammad Faisal

There is a section on cheese. This hadith is a Sahih Muslim Hadith 687, Narrated by Abu Hurayrah (radhiyallahu anhu).

"Performing ablution in the mosque, he said: I am performing ablution because of having eaten pieces of cheese, for I heard the Messenger of Allah Ta'ala say: Perform ablution (after eating anything) touched by fire."

I would like to know what is meant by "touched by fire" and why should we make wudhu after eating something that is touched by fire?