What are the reasons that people get offended when you talk about hiv/aids?

Homophobia? etc: Many people associate aids with behaviors of which they disapprove, that are socially unacceptable to them. Two main ways HIV is spread is IV drug use with shared needles, and sexual contact. Much of the early publicity was with gay male sex, and many people are homophobic even today. Iv drug use is, of course, also frowned upon by society. Aids is associated with these and so makes some upset.