The paradox is a common one.
One of the lovers is sick.
The other is not.
Do you refrain from kissing that person, so as not to infect him/her?
Do you "wuv dem sooooo much dat" getting sick is worth the few precious kisses and you infect them anyway?
Well, let a cold hearted economist provide some insight.
Say one of you is sick.
This precludes you from kissing your beau/babe for the time that person is infected with the disease. That person suffers, and you don't get to kiss him/her. But inevitably that person will recover and then you can get back to "sickness-free kissin' time."
But if you are of the "kisses are worth the sickness" philosophy, then you too are going to get sick.
If you get sick and the other person recovers, then all you have managed to do is simply put that person in the exact same position you were in, THUS PREVENTING THE EXACT SAME AMOUNT OF KISSING.
THEREFORE (thanks to my SAEG (tm))
It is best to let the person be, NOT KISS YOUR BETTER HALF, have "girls weekend" or "guys weekend," and let them fully recover, for if you do, then you
1. won't get sick
2. won't lose out on any more kisses than you would anyway (because of the duality of sickness)
3. and will halve the sick-kissing time, replacing it with "healthy-kissing time."
I am glad I have solved this life-long paradox, making life easier for millions of future generation people.
You may send your thanks by shopping at Amazon or buying one of my many SAEG (tm) books.