I dunno, should I keep going? I'm not one that often complains about these things, but "rape as backstory means you're going to hell" is a bit icky.
Bela didn't go to hell because she was raped. She went to hell because she made a deal with a demon to get her parents murdered. Even in real life. hiring a hitman to murder anyone for whatever reason that would get that person in prison.
I'm very surprised you are such fan of the character. She was mostly disliked by the fanbase because every time she appeared she made the Winchester boys look like idiots.
In this show there are rarely any happy endings for supporting characters. This is something you need to keep in mind.
If you have made it all the way to the end of season 3, you should at least check out season 4. Many fans consider season 4 to be the best season of the series. It would be a shame if you stopped watching before seeing that yourself.