middlepath, you ask some very interesting questions:
!. why do I deserve such a great girl?
2. will she be able to deal with difficult issues
Firstly understand that everyone is deserving. If Hashem sent you this amazing gift then who are you to question his wisdom? Why shouldn’t you be as deserving as anyone else? Maybe you are exactly what SHE needs to complete her? Someone honest, down to earth who has seen the best of times and the worst, who knows how to appreciate what Hashem gives and also knows that Hashem can just as easily take it away. Someone who can teach her that life is not always a bed of roses and yet you can meet life’s challenges and still turn out to be an example of what Hashem wants and expects of us.
Your second question is more complicated and not so easy to answer. Unless you yourself have serious conversations with her, there is no way of knowing what personal challenges she herself has experienced in the past. Even though everything looks very rosy that is not always the case. In addition, even though she in her young age might not have weathered many difficult challenges she might have aided or supported those who did by means of cheesed and especially if she had friends who went through hard times. Just because she looks or seems perfect that does not mean that she is a china doll that will crack and break if shaken up a little too hard.
Through getting to know her and hearing her speak about her own experiences you will learn to understand who she is what she is all about. What she is capable of what she still plans to accomplish.
I hope this helps somewhat. Hatzlocha.