Why do I experience men not respecting my boundaries often?

I have often heard that I’m good looking and without sounding conceited I know I’m pretty. But I have often experienced men not being able to keep their hands to themselfs on dates and in like group situations where friends always need to step in. I’m a pretty quiet person that keeps to herself and I never dress in a certain way that could invite this behavior. I’m a Christian as well and I want to wait till marriage, when I tell men this they always seem so happy and then still try to see how far they can go. I’m now starting to doubt myself a lot and I often think it’s my fault somehow.
I am tired of sticking up for myself and dealing with certain trauma’s men have caused in my life.
Why does this happen to me and how can I determine who is right for me?
Why do I experience men not respecting my boundaries often?
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