The Society for Industrial and Applied Mathematics. There are also important contacts to be made by electronic mail. There is also a mailing list for women in computer science, and one for members of the Association for Women in Mathematics. No student gets through graduate school without experiencing a significant amount of stress. There is always too much to do, and not enough time to do it.
Students doubt their intelligence, their creativity, their motivation, and sometimes their sanity.
This is normal, and probably unavoidable. But there are certain factors that will make your life smoother. Use them as sounding boards, as shoulders to cry on, and as non job-related companions. And make sure that they can rely on you for the same things. The support of your family is a great resource.