Betty wanted Peter to marry her, but she kept seeing him with Liz Allen and so became jealous and started dating Ned, eventually marrying him for the stability, but they had marital difficulties with him being a foreign correspondant and her being a tart. She had an affair with flash, tried to shag Peter at one point. Got back together with Ned, he was 'revealed' to have been the Hobgolin (another fake, like Lefty Donovan, Flash and others. The real hobby was Roderick Kingsley, a fashion designer who hired MJ at one point, but this wasn't known till years later). Anyway Ned died in Spider-Man vs Wolverine one shot and Betty ended up having a bit more of an affair with Flash Thompson, then briefly joined the cult of love in Web Of Spider-man (issue 30 something I think), which caused the break-up of her and Flash. She changed from secretary to journalist (although since the appearence of Glory Grant in the 1970s she didn't really do much secretary stuff).
I believe she tracked down Kingsley and proved her dead husband's innocence in 'Spider-Man: Hobgoblin lives' a mini-series circa 1997. She's mainly a peripheral character these days since nobody really knows how to write her, mainly serving to intermittantly want to sleep with Flash or Peter.
Oh and she still blames Spidey for the death of her brother in Amazing Spider-man issue 8 or something. In actual fact it was Dr. Octopus' fault though.
The real question these days is of course where is Sha-Shan and how the hell can she possibly fit into continuity given her and Flash's backstory
