By making the value of life contingent on the quality of life. Euthanasia implies that the lower your quality of life, the less valuable it is. This can lead to all kinds of abuse.

Technically it's not an ad hominem fallacy

It would be an ad hominem fallacy if he claimed that your position is wrong because you're an idiot.

He simply called you an idiot without making any claims about your argument. This means that he did not commit an ad hominem fallacy, he just insulted you.

Probably not.

To say that one is both pro-life and pro-choice results in the following - I believe that all innocent human beings have an inherent right to life which we must protect. The unborn fetuses are innocent human beings. Therefore we need to protect them. However, I also believe that mothers should have the right to kill their unborn children for whatever reason (medical, economics etc). So, while I think that murder is wrong, I understand that other people may want to kill other people for whatever reason.

I do not want to shove my beliefs down others - if a mother wants to kill her children, that's not my business. But nevertheless I think fetuses have a right to life.

That's one example, but these things vary between different nuances in both pro-choice/pro-life views. Contradicting elements may also arise: a fetus has a right to life (pro-life), but doesn't have a right to life (pro-choice). A fetus is a human being (pro-life), but it is not a human being (pro-choice).

What? I agree that a zygote is not a fully sentient being. I just don't think it matters.

What is sentience and why is that the most important criteria for deciding whether someone has a right to life or not?

You don't need to be sentient to be alive.

While we're here, can you define sentience? Can you also justify why sentience in particular determines moral worth?

It was a rhetorical answer to a hopefully rhetorical question.

When pro-choicers admit they're pro killing innocent human beings I guess.

And there are christians, who do meet the goals they've set and I too can point to countless examples. Consequently, there are countless christians who cannot live up the moral duties that are expected of them for one reason or another. Yet in either case, we must distinguish a philosophy from its adherents and judge the philosophy on its own merits.

In the same way, I can't sweepingly condemn feminism simply by pointing at the likes of FEMEN, Chanty Binx and other rabid man-hating women. Why? Because there are respectable feminists with legitimate views as well, not to mention that feminism is a distinct abstract view that needs independent investigation.

Your view of christianity is simplistic and juvenile. Given that you're already developed very clear preconceptions about christianity, there is nothing I can do to change your mind.

Teenage pregnancy and the spread of STD-s is the direct outcome of the liberalisation of sexual norms. The more marital institutions have weakened, the more promiscuity has risen and with it all the ills that come from people having sex everywhere. So while it's commendable that teen pregnancy and the spread of STD-s are lowering in some areas, it can be argued that these problems were caused by the weakening of christianity and of its institutions (such as marriage) in the first place.

Teen drug use - again, depending where you look. What about non-teen drug use?

Obesity - certainly, low-quality food plays a part here. However, there are also no limits in a secular consumerist society, how a person should control their appetite. Especially when you have rabid social justice warriors calling an end to fat shaming in the name of a more diverse and egalitarian society.

All while society becomes more secular (aka less Christian).

The onus is also on you to demonstrate, why these problems are lessening because of secularism, and not because of mere rising living standards.