Hi gjkopriv
Surprising to me, that does make sense.
Something that might help you if you find yourself rebuking yourself over this is to look at the history. I think that's the easiest.

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I don't think it's uncommon for a pwBPD to be dishonest about their marital status. That is quite a disconcerting relationship history. It's not obvious to me what's truthful or not truthful. It might all be lies, it might all be true. I think what would be helpful is not to focus on what happened, but to see the effects and results of it.
She has a messy relationship past. What you describe is a strong definition of messy. She then expresses she wants a traditional relationship. That may allow a non like you to step in. If you have some "saving" tendencies, you might even be drawn into this sort of situation.
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Regarding knowing the what and whatnot a pwBPD is capable of doing, it might be better for you to prepare for the worst. Something that helped me was to assume someone out-of-control and to expect actions from that. While it may not be accurate, I found it very helpful to me, especially when I didn't have time to do nitpick management of the pwBPD. Sometimes with a pwBPD, things just move so fast you don't have time to figure out what's true and what's not. It seems simple, but it can be difficult to adjust to, because most of us didn't assume a disordered person at the relationship's start. After a relationship, looking back with this set of eyes can help you find understanding by you, of both you and your ex.
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I don't think rape stories are uncommon amongst pwBPDs.
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How can you avoid things like these in the future?
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