I haven't seen the movie but the English line quoted out of context by itself sounds like a twist on quitting any addictive substance, like heroin, opium, or in this case, "you". So I wonder why the core of this shouldn't be a simple 止める.

This is my long-winded way of saying I think the original いっそやめられたら… is quite satisfactory, esp. given the limitations on what you can do in subtitles.

"I would even end our relationship (lit: cut my hand free) if I could."

That sounds more like a MetaFilter flameout.

yameru as the verb is fine with me, but I think you need the "you" in there. I think "quit you" is marked in a way that "quit heroin" or "quit my job" isn't (the variants of that line all over the internet suggest that I'm not the only one struck by it). So, maybe it's my Indo-European bias, but I think いっそやめられたら… is too vague. It could mean "I wish I could just quit meeting you like this" or "I wish I could quit wanting to have sex with men" as easily as it could mean "I wish I could quit YOU"

Not having native intuition, I can't tell if something like お前なんかいっそ止められたら… or いっそやめられたら…お前を would be so marked as to be jarringly unusual or ugly (redundant), but it seems to me they'd convey more of the original feeling.

That "limitations of subtitles" line (of reasoning) has been (over)used to cover a multitude of sins for too long, in my opinion. (No animosity directed at you, Mark!)

Who did the subtitle translation, by the way? (I haven't seen the movie, and am not likely to given our deplorable theater situation out here in the sticks.) Not my "darling" Natsuko Toda, I hope!

(I loathe that woman.)

Gee, I'm always late for this interesting discussion...

Just for a quick note: theoretically, I believe 止める can be tomeru (as in "I stopped my car") and yameru (as in "I quit smoking"), but very often we use 止める for the former and やめる for the latter. Don't know why. So, いっそ止められたら sounds OK but looks a little bit strange to me. Very Japanese. -- HJ