That's an appalling thing to say - "too positive about your situation"? She's prefer you to be, what, crying and miserable?
She is probably intimidated by your resilience and independence - and maybe jealous? I think sometimes friends who have been in a serious relationship for a long time can slightly envy single friends their "freedom" - good friends are honest about that. (One of my lovely friends has been with her husband since she was 16, and always says that though overall she is glad to be with him still, part of her would love the excitement of a first date, first kiss etc).
But in people who are less open hearted, I guess it can manifest in this sort of pissing on your parade, which is NOT what a true friend does in my opinion.
I do find some male friends (in particular) can become hyper-protective and keep stressing the importance of safety measures when dating more than is needed. I find that one a bit difficult to respond to because yes, it's good to acknowledge dating can be dangerous for women, but take that too far and it feels like being told what we are and are not allowed to do - it's quite paternalistic. I think as intelligent women we all know the risks, and it's up to us to decide how we handle them, which is a very personal.choice.
One of my friends, for example, who is open to NSA stuff, has guys over to her house for a first meeting. That's not a risk I would take personally, but she knows the risks, she's an adult, she does things to negate them (texts me or another friend before and after....) I think it would be patronising and unnecessary for me to keep going on about the risks - she's not stupid.
Sorry, that was a bit of an essay......