In terms of friendship, the answer is obvious–we keep a distance–in business, however, there is the question as to What obligation the modern Torah-Observant Jew has towards homosexuals who are open about their sexuality, since in the Diaspora we do business with a variety of individuals and we are not allowed to discriminate.
In Leviticus 20:13 we learn that Hashem has instructed Israel to impose the harshest of all possible punishments for the sin of homosexual relations among men. My question is this: If the Halacha does not change with the times, are we to interpret the same punishment is still valid today for a modern day Israel –which is a nationalist state and not a Theocracy? Is this punishment not reserved for a Theocracy whereby the Moshiach is our leader? BECAUSE…..If that punishment were to be followed, it would be devastating to Israel’s relations with other countries–especially Europe– which has a more tolerant policy, and that lack of business that would result would create further damage to our ability to do other mitzvot. Therefore, what is Modern day Israel obligated to in terms of relations with sexually immoral individuals (many of whom are Israelis)