what causes it and why does it affect the people around us?

i don’t get it.
if you are going to act like pigs and are going to have homosexual relationships or premarital sex, you have to be prepared for anything, that includes the possibility of getting a sexually transmitted disease.

Recurrent Yeast Infection Cures, Causes and Prevention
A person may be said to be suffering from recurrent yeast infections if he or she is suffering from this infection for four or more times in a year. A yeast infection is the over growth of yeast in ones organs. Normally yeast can b found on a healthy [...]

If your fiance got HIV or herpes or any other sexually transmitted disease from drinking after someone, or anything other than cheating… would it be ethical to break things off, just because you do not want to sleep with someone who has a sexually transmitted disease that could threaten your life?

Is it possible for a woman to have endometriosis for a number of years before having it diagnosed? If so, will that interfer with child birth ( premature birth and miscarriages) and does it cause discharge and excessive clotting while having your cycle?

How are a) Bipolar Disorder, and b) Premenstrual Syndrome diagnosed? Are these things determined through, say, readings of brainwave frequencies, blood tests, just plain old therapy…? Is it common to misdiagnose these conditions?
Thanks