There are many ways to meet new people and get involved at the University, both within the department and beyond. Below lists all of the social/extra-curricular outlets within the main campus; organizations within the City of Guelph that students can join have been excluded. You may wish to refer to the City of Guelph page if you wish to search for city-wide social outlets.
Your research is important, but so is everything else outside of it. Graduate school can often be demanding. It is vital to maintain a good life-work balance, but if things get too much, and even social outlets aren't enough to help, the University of Guelph offers many resources to help and meet your needs.