Marion Ravenwood and her Amazing Titanium Liver.
That should be a comic book title, or at least a really killer act at the local three-ring circus. Sadly, Marion has to perform that trick in her Himalayan bar: drinking Sherpas and brawlers under the table despite weighing about half as much as they do. Frankly speaking, she's really not one for alcoholism. We only see her drink a couple of times and she pretty much ignores booze the rest of the time. So we're thinking she's not a compulsive drinker; she just has an amazing ability to avoid getting drunk, even when she downs enough liquor to poison a musk ox.
The Bad Boyfriend Blues
Frankly, we wouldn't much blame her if her drinking were heavier. Somebody did her wrong once, and when said somebody comes sauntering back into her bar like nothing happened, it's bound to make even the most teetotaling individual start reaching for the bottle. So Casablanca.
Dr. Jones loved her and left her, and judging by what the film implies, she was just a little too young for that kind of crude treatment. "I was a child! I was in love! It was wrong and you knew it!" she screams at him, right after decking him in the face. So she's got some deep wounds to deal with, on top of running a bar for the locals halfway up a ridiculously large mountain.
Tough Gal or Damsel in Distress?
The good news is that she's not the type to go weak in the knees. A tough life makes for a tougher gal, and when danger rears its head, she's more apt to stare it down with a snarl than scream for help. "Listen, Herr Mac," she growls to the scariest guy in the whole wide world. "I don't know what kind of people you're used to dealing with, but nobody tells me what to do in my place." Granted, she delivers a couple of shrieks here and there (she apparently doesn't like mummies much), but she saves them up for the really special occasions instead of dropping them every time a little problem shows up.
The filmmakers balance that toughness out with traditional damsel-in-distress stuff. She still needs saving, she's just not going to sit around and wait for it—but they want us to know that she's different from the earlier serial movie heroines who came before her. They can put her in danger (thrown into a pit full of snakes, stuck in a locked plane on an exploding tarmac, the whole "pluck your eyebrows with a flaming hot poker" unpleasantness) just like we expect, then have her react in an entirely different way than those earlier movies. Raiders uses her to send up the old clichés a little bit even as it embodies those same clichés: a slick little way of having its cake and eating it too. That's all a little meta, though it's a no less important part of Marion's personality.
Similarly, her wounds are important because they give Indy a chance to right some past wrongs. She's a walking, breathing reminder that he was once a pretty big jerk and that he needs to change his ways if he wants to be a proper hero. It takes a while—seriously man, you're gonna just leave her in the hands of the freaking Nazis?!—but he eventually figures out that she matters more than the Ark, and the pain he inflicted on her could really use a Band-Aid or two. Marion's the embodiment of his past sins, the mistakes he's made, and the injuries he's inflicted. Healing her pain is the real purpose of his quest, though he's unaware of it until the very end.
At least he figures it out in time ("All I want is the girl," he tells the Nazis while pointing some seriously heavy ordinance at them). Marion is exactly, precisely the kind of gal you want on an adventure like this: smart, plucky, able to crack some skulls with a frying pan if need be, and always ready to drink the local bad guy right under the table.