We had one, maybe two people in the audience who laughed at exactly the places you mentioned. They were up front and I was in the book so I don't know what the issue was.

As far as Heath Ledger's makup - he's outdoors all the time, herding and ranching in very harsh weather. Crusty is exactly how you look.

I've read over 100 comments/reviews at imdb and almost universally, gays feel the problems depicted are societal in nature, straight (usually) women find it's Ennis himself that's the cause.

I'd say it's a combination. Ennis is an emotionally closed off, reserved person. That's his essential nature. But he does open up with Jack (we especially see it in that flash back to an earlier time they last time they are together.) But because society and especially his father have drilled it into him that this is wrong (and life threatening besides), Ennis refuse to reach out to the one persom he loves completely. So, the problem is Ennis but the initial cause are outside of Ennis.

Teh again, I think that's what makes the movie universal, It's our own oersonal prejudices, emotional failings and cowardices that speak to us all, because all of us have issues that hold us back.

I tkink the last line means a lot of things. Certainly what you said, but also that he swears he did love Jack. Something he never admitted before.