This is an overly simplistic look at the Bible, which is giving you a false picture of Christian morality.
From the bible, it says a man can sell his daughter into slavery, which is obviously perfectly fine with god. I don't get christian morality though, as selling your daughter to slavery is kosher but having sex with your fiancee is sin?
Forms of slavery were tolerated in the Old Testament as a means of paying off debts. However, this was to be for a period of no more than seven years, after which the slave was to go free. In the case of a female slave, part of the agreement to enslaving her in the first place was also a promise of betrothal. She would be betrothed either to the man who bought her, or if he was old, to his son. If he reneged on the deal, she was to either go back to her father, or to be set free. This was to maximize the possibility of finding her a husband, which a mature woman needed in that society, lest she become a beggar. Note that this is within the context of Hebrew society. The New Testament does not call for selling anybody as a slave, and in fact forbids it (1 Corinthians 7:23, 1 Timothy 1:10). It did not call for abolition outright because it had to work with Roman society at the time, where slavery was pervasive. In fact, slavery went obsolete in Europe by the High Middle Ages, though it tragically was re-instituted with colonizing the New World (and without regard to what the Bible says on slavery).
Sex with the fiancee is a dangerous practice because the knot hasn't been tied yet. Without that, there's no life-long commitment. Given the many failed engagements that have happened, I'd say it's a good idea to abstain until actual marriage.
Genocide is okay, but abortion is murder.
Genocide isn't okay. God called for a select few nations which were so exceedingly wicked as to practice child sacrifice to be exterminated. If any culture deserves that, it's a culture which ritually burns babies alive and literally puts a child in the wall of a house which is being constructed (which the findings at Ras Shamra confirm were prevalent in the region at the time of the Exodus). But other than those cultures which were specifically named, there is no call to exterminate a people.
And yes, abortion is murder because human life is precious. A fetus is innocent (it committed no sin) human (undeniably human DNA unique from the mother) and alive (otherwise he or she would be stillborn, of course). Therefore, we don't have the right to wantonly end that life. People may bring up questions as to when the fetus receives a soul, but since we don't know the answer to that question, better to err on the side of life. The only time when abortion should be condoned is in cases where it is the only way to save the mother's life, such as an eptopic pregnancy.
How to reconcile this? Easy - “Whoever sheds the blood of man, by man shall his blood be shed; for in the image of God has God made man. " - Genesis 9:6
In other words, if you kill somebody, what goes around comes around.
Christians are supposed to love others as themselves and treat them as such, but then they condamn everyone else who does not believe exactly as they do to eternal torture.
Christians are told to be loving and kind, so they tell everyone they are a worthless sinner whom does not deserve to live.
Personally, telling people that they are worthless sinners who deserve hell is not how I spend my day. Yes, we all fall short of the perfect standard that God has set for us. Yes, we have all rebelled. Yes, it's either Heaven or Hell, and none of us deserve Heaven. I don't deserve Heaven. I deserve to be eternal kindling. But Jesus gave me a chance that I don't deserve by taking the punishment I do deserve. It's available to all who put their faith in him, turn from their old ways, and obey him. People ought to at least know about this way of escape. But if they are absolutely closed to hearing about it, there are better ways that I can spend my time.
