What Pin said, and please
don't make stories/narratives in your mind.
I honestly though feel like there is nothing going on and on that note:
You are simply projecting your fear onto her. You should tell her. It can be difficult to love and to be loved, it's not easy, and at times it can be the hardest thing. Also, remember that she reassures you and that in itself is a beautiful thing as not everyone is ready to take into account that people don't have a clean slate, or are willing to go through the ups and downs.
Allowing someone to love you is also sharing your struggles whilst not being judged, you two seem to have that (when you eventually share).
Share with her your fears and thoughts when they come up which btw is much better than to approach it by needing reassurance or by necessarily asking questions that sprout momentarily from fear: "would you ever..."&c.. that honestly just creates a vicious cycle as the reassurance can only last
that long. So, aim for the root of it.
Eventually you are also just going to have to decide to share your vulnerability with her or not. You can fear for that emotional rejection all the time or you can later wish you had just gone for it... still, you seem to know that ..Like you said, you always eventually share.
Also, don't forget that doubting someones sincerity and being sceptical in a relationship when they are sincere is playing with fire. If done repeatedly, it can quickly become an emotional rejection even abuse in some cases. She needs to feel safe too y'know.
I'm glad to see that you acknowledge that this might just be a projection, treat it as such.
Still,
If something is going on:
Leave or work through it together.
Either way, what's the worst that could happen?
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Question, are you ready for a relationship?