Answers:
Tonsillitis usually spreads by contact next to the throat or nasal fluids of someone who is already infected. So, to protect yourself as much as possible, do the following:
1. be painstaking just about handwashing and use soap! (most infections are spread because of poor hand hygiene)
2. your partner must use tissues for coughing and sneezing (don't agree to those droplets escape into the upper air or onto surfaces)
3. do not share silverware or drinking glasses/cups
4. no kissing or oral intimate contact
5. you might want to use a zinc product to further protect yourself (such as zicam nasal swabs)
Just remember, handwashing will be your biggest form of protection. Good luck!