How to deal with a colleague who always puts you down? I am just starting out my PhD which will take 5 years to complete and I am dealing with a person in my own research group who cannot stop putting me down every chance she gets.

In our research department in neuroscience engineering I guess she would be considered a very ambitious person. She has good grades and has some papers published despite only being in the university for about three years. But she has a very bad personality and constantly attempts to put me down by comparing me to some of the other researchers in the department.


For example, she will come up and say I know so and so who is in the
same year as you are and he already has papers published, you don't. 
Or I know this other person who did really well in a class and even got
the professors recommendation while you are only an average student. 
She will non-stop ask me for my GPA as an undergrad, and how I am
doing in my courses. I thought she cared about me at the beginning but I am realizing that she is only exploiting my weaknesses. 
She will also ask me about my research focus and tell me whatever I
am trying to do has no value or too small scale. She will openly laugh about my research plans in front of other people and say that it has no value.
Even when we first met she asked me about my background which I said
was in industrial engineering and she just kind of laughed because she
was in some sort of advanced research program which is in her
opinion more prestigious
Finally, she has no moral qualms doing all the above in front of other people. In fact she only does this to me when other people are around. 


Worst of all is that she is making an assumption in almost everything. I have a few research papers published, just not at the current university so it is not listed. My GPA was dragged down during first years of undergrad but it picked up and at the end I had a 4.0. Plus she is not doing too well either, only with a few minor publications on very specific applications, and she is only known for certain speciaties and not much of a generalist and knows very little about the fields immediately outside of her research. But do you think I ever tell her this? Call her out about her lack of creativity? Or ask her about her GPA and the courses that she does bad in just so I can tell her that "Mr X is doing much better than you in that course"? Of course not because I am a decent person.

We are in the same research team. We should be working together and learning from each other, yet she behaves this way to me. I was so relieved during first few months when I started out my research because I have heard so much about these kind of people you encounter during graduate school yet I have not even encountered one and everyone is so helpful, but there she is. Since we cannot move forward in an amicable relationship, what is the best alternative for me? Am I being too sensitive?
I favor the Confusingly Positive/Neutral Response in these situations.


"So-and-so did Awesome Thing and you --" "Wow, that's great! When will it be published? I'd like to read it."
"What was your undergrad GPA?" "Uh, I don't even remember. It got me in here, though, and I love it here!"
"Bah, what you're doing is garbage." "I'm finding it a lot of fun, and learning a lot!"


When she pulls these stunts in front of others, you will look infinitely classier than she for refusing to play the game.