12.
1. To treat somebody with a dose of his own medicine
2. Health is not valued till sickness comes
3. No herb will cure love

13.
1. I agree with this proverb because it doesn't matter if you're rich or poor: when you suffer from incurable illness you will die anyway and the wealth will become useless. 
2. I do not completely agree with this proverb because in some cases people never forget about something they've been hurt by. Time may blur some irrelevant memories, but the real, huge pain will never leave the person.
3. For me, this proverb does actually make sense. A person who has been through something can help other people to overcome some fears or give an advice based on his or her experience.