Is には being used like "if" here?

Question

From Bakemonogatari, A is trying to convince B that they should trust someone, but B is not so sure:

A: だから一応信頼していいとは思うぜ
僕一人の証言じゃなく羽川もそうだっていうんだから
B: そう … でもね阿良々木くん
彼のことをおいそれと信じるには 私は今まで何度も何度もだまされ続けているわ
だからそんな楽天的なふうにはどうしたってちっとも思えないの
A: That's why I think he's more or less trustworthy. It's not just my testimony. Hanekawa says so, too.
B: I see. However, Araragi-kun... If I could believe him that easily, I would have been tricked countless times.
That's why I can never have such optimistic thoughts.

My attempt without any sort of conditional:

In order to believe him on a moment's notice, up until now I have been deceived countless times.

But of course, she has not been deceived because she never trusted him in the first place. But to get "I would have been deceived countless times", why would you not say 信じていたら or 信じていれば? This is most surprising to use には "in order to" like this because this seems like a counter-factual kind of sentence, but typically the verb needs to be in the progressive form like I wrote. I get that the だまされ続けている is probably needed because she's marking the state she "would be in" now, but the beginning puzzles me.
What is the nuance of using には like this?

Answer 1

There is an (invisible) period right after this には. That is, "彼のことをおいそれと信じるには" forms an independent sentence.

彼のことをおいそれと信じるには。
We should not trust him easily/blindly.

It's short for something like 信じるわけにはいかない, 信じるには至らない, or 信じるに足りない. It's in the same vein as 行かなくちゃ meaning "I must go".

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EDIT:

If it was one sentence, she would have used the ～には～過ぎる ("too ～ to ～") pattern and said like this:

彼のことをおいそれと信じるには、私は今までだまされ過ぎているわ。

I've been deceived too many times by him to believe him that easily.