You have 'faith' that she is a good friend because (hopefully) she has demonstrated that to you. You have good reason to believe that the good friend status will continue. That is only one kind of faith which can also be called trust. It is justified and has a basis.
Another kind of faith is the kind that religious people talk about a lot. It's the kind of faith where someone you trust tells you something extraordinary without any evidence to back it up and you have 'faith' that it's true contrary to all available data.
The first kind of faith doesn't actually need to be called faith, it has other useful names, the second kind however, you don't need to have that, it really doesn't serve anyone.
Another kind of faith is the kind that religious people talk about a lot. It's the kind of faith where someone you trust tells you something extraordinary without any evidence to back it up and you have 'faith' that it's true contrary to all available data.
The first kind of faith doesn't actually need to be called faith, it has other useful names, the second kind however, you don't need to have that, it really doesn't serve anyone.
