Re: gay marriage, I really don't understand the opposition. I admit that my lack of interest in who wants to sleep with whom is remarkably low if I'm not one of the parties involved, but my puzzlement goes further. Nobody is going to force somebody to marry a member of the same sex. Nobody is going to force any particular person to officiate at any given wedding. I have heard proclaim that marriage exists entirely for procreation, but those same people don't object to people well past child bearing age (or sterile for other reasons) marrying.
Moreover, if we believe that it is good public policy to encourage people to form stable relationships, it makes no sense to tell a significant percentage of the population that they're not allowed to do so.
Re: abortion, I want to focus specifically on late term abortion because I think it highlights a problem in the way people think about the subject. The anti-abortion crowd tends to assume that abortions are performed on frivolous young women who suddenly decide they don't want to be pregnant. While there certainly are a handful of instances that might qualify for that category, late term abortions under those circumstances are extremely rare if not nonexistent. The real reasons for late term abortions are either grave danger to maternal health or severe birth defects which often can't be detected earlier. I'm also disturbed by reading assumptions about what constitutes such a birth defect. In general, we're talking about things like anencephaly (i.e. no brain - and no, zero, nada chance of survival), not things like having the IQ of certain extreme right wing politicians.
My point is that there is no actual need to restrict late term abortion because any sensible restrictions already make exceptions for the cases under which it happens today.
More generally, I stand in the large camp of people who want abortion to be safe, legal, and rare. That means providing for effective contraception to be widely available, educating people on contraception (and not just abstention), and providing support services for women who do wish to carry pregnancies to term but may not have appropriate economic and social resources to do so.