Oooh. He has such hatred for James, but Snape keeps protecting Harry. Perhaps because of his mother's eyes. So, when he told Voldemort about the prophecy and Lily was killed (I must add I think Lily and James are alive), he came to Dumbledore. Maybe that is why Dumbledore trusts him. Snape loved Lily, and love is the greatest power.....my head is spinning!
As to Harry being a horcrux (his scar) I was reading on another board where they listed the 7;
Ring - destroyed
diary - destroyed
locket
cup
snake
something of Ravenclaw's
V himself
That makes 7 without Harry.
As to his parents not being dead, the protection Harry has had for the last 15 years he's had because him mother loved him enough to die for him. That protection wouldn't be in effect if she were alive.
Does anyone think that Harry's Aunt may be a squib and that's why she knows so much about the wizarding world?