It might be wise to trust your instinct here and just continue to be there for her and earn her trust. Going all in early on would likely scare her off.

Gradually prove your love over time. Show her that you love her by doing and saying small kind things and being there for her even if she doesn't seem to need it. Start off small and increase as time goes by.

She might be closed off and act independent, but sometimes, people like us are often crying inside our head and wanting to be understood when we push somebody away or shut somebody out, yet we're afraid to let you in. Keep being there for her and offering her support.

Keep showing her love and your actions will prove that you are there for the long haul.

Sorry I couldn't be more of a help