Many older people still think consider incest and masturbation to be taboo subjects.

Many things in life is considered Taboo from one culture to another but in general Incest is Taboo, this goes back to even the Bible and before then.

If something is taboo, it means that there are groups or cultures that frown upon doing that action. For example, in some areas, adultery and smoking are prohibited.

Blood relation equals incest, law relation equals strange. Either way it's taboo and your gonna have to accept that if you "love" your uncle.