How can a Christian say "hell might exist because these certain people are horrible"? Have you earned your own salvation, then? Are you good enough to not only pass God's judgement, but to elect yourself the judge over the sins of other human beings?
Yes, it is the Christian's duty to love and not to hate BECAUSE OF THE GREAT GRACE THAT THE LORD HAS GIVEN US! Do not respond to the hate of sinners with hate and contempt, but first consider yourself the worst of sinners (1 Timothy 1:15) and leave it to the Lord to judge.
PLEASE do not find your justification by comparing yourself to other sinful and hateful people and do not lead others into doing the same thing. It is only Jesus Christ who can suffer your punishment for you and make you clean, and he is has the power to change the hearts of the people that you've mentioned, so pray for them and do not damn them.