>I don't see the suicide thing as an issue
Oh, it's a big one. It's the film's Jump-The-Shark moment. If you introduce something that extreme as a plot device, and then don't resolve (or even address) the issue again, you've created a massive roadblock, and something too stupid to be ignored.
It's like the film Legend of Lylah Claire. Seen it? Kim Novak plays a Miss Nobody, tapped to play The Greatest Star Of The 1920s Who Died Mysteriously. As written, she gets so "into" the part that she "becomes" Lylah. Somehow, while in the editing stages, the disastrous decision was made to add a supernatural element, and a booming, male sounding, German accented voice was dubbed over that of Miss Novak in certain scenes. Thing is, as shot, no one reacts at all to the voice of satan booming out of Kim Novak. One has to accept that a pretty blonde woman would suddenly begin speaking with the voice of a German man, and no one would comment, notice, or ask why. And we hit the roadblock of stupidity and the film becomes unwatchable.
And so it is with Rose dangling over the propellers. Yeah, lots of people (masochists, who channel their proclivities into 'nurturing') fall in love with people they've 'saved' (and you KNOW how well that usually works out) but usually not within 30 seconds of foiling someone's suicide attempt. There are a number of reactions that surface in such cases (dont get me started) ranging from anger to shock to fear to disgust. Generally, an erection isn't one of them. Not in the world of the sane, anyway. Yes, long term, Jack COULD have fallen for Rose, etc, but in the time frame that the film allows, his immediately pursuing and sleeping with a stranger who he met while in mid suicide attempt, reduces him to someone on the psychological level of....Ted Bundy.
>and their behavior should be judged accordingly on that fact!
Sleeping with a stranger one met while she was trying to kill herself, within hours of the suicide attempt, was weird and unwholesome in 1912. It's weird and unwholesome now.