The tears of the classmate who came from Philippines

That was not the first time when the eyes of my Filipino classmate Vanessa turned red.
The first time was when the other Chinese classmate Yufen left for going back to China. Well, on the surface, it seemed that she just wanted to go back to China for a while, but the actual reason for her departure was that she could not catch up the progress of the class. Anyway, honestly speaking, I never recognized how close was the relationship between Yufen and Vanessa, while Vanessa never hided her laughter whenever somebody made obvious mistakes while doing oral exercise in the class.
The second time when I saw the tears of Vanessa was when the Polish boy left for whatever reason which I don't know, probably for some special study in his home country or so. The tears turned out in such a sudden and flourishing way, which really surprised me, because I never believe that people could build up close relationship in a short time. Impossible. With the fact I saw from Vanessa, I would have to reexamine my realization.
I was astonished by her tears again last Thursday, while she was saying Goodbye to everyone. While receiving the present from her, I thought that it was for the Christmas. Oh my! I had no clue that she was leaving. So embarrassing.