Why I am still a Christian.

[Red Celt]

It's obvious St Paul's teachings conflicted with the original teachings of Jesus and the Apostles.

That sentence made me want to kiss you.

The number of debates I've had with Paulians who called themselves Christians... it's insane, the degree of denial that some people are in, it really is. If I shared the Christian viewpoint (about Jesus actually being the son of God), the disparity between the message of Jesus and the message of Saul of Tarsus would leave me wondering if the voice that he heard on his way to Damascus wasn't actually that of the devil. How can any Christian/Paulian really know the source of St Paul's message?

As for the rest of your post... you're not alone, in the UK (or, I'm sure, elsewhere in the world) when you say that your belief-set is a cultural one, rather than a religious one. In Terry Pratchett's Small Gods, the message was a clear one... people worship the church, not the god(s). Culture is a prevalent meme; but that does not make it an excusable one. Bad things happen because zealots use the numbers of "worshippers" as justification for their right to impinge on the rest of society.

You are still young. As you age, please keep in mind that there are secular groups to which you could switch your loyalty.