See...what I hate about the left is their intolerance of any stream of thought that leaves the reservation, whether it’s pro-life, pro-religion or pro-capitalist. I am not conservative at all on social issues, but I happen to respect other peoples beliefs, and like the fact that we can still agree on principled issues.
The left worships the state. Any thought that threatens the ideal of state power is suppressed either with actual power (lower grades, law suits, or even imprisonment in tyrannical states) or social harrassment like being insulted or shouted down. From a conservative perspective the left's support of things like abortion, use of embryos in research, homosexual marriage and the like makes sense in that the family and the church is a bulwark against state power -- the family and the church are alternate centers of loyalty and power -- and so the left wishes to destroy them.
Things like sexual morality, where the left tends to encourage what the conservative views as immoral, I think can be seen in the context of the same attack on church (crudely put, you can listen to your parents and your church or you can get laid, you choose, Mr. 18 year old boy and Miss 18 year old girl) and attack on family (crudely put, why buy the cow when you can get the milk for free?) and also a way to weaken the individual through undermining the self-reliance that comes from good living, good morals, and personal self-discipline . . . and with weakened individuals the state steps in and can more easily dictate. This is why I think the left supports "social issues" like abortion, homosexual marriage, divorce, embryonic research and so forth. It's not about "freedom" it's actually about the reverse -- undermining alternate powers to the state in the individual, the family and the state.