Relationship advice? Please help?

[Stuart]

My gf and I were together for 3 years and we then split up for a year just before she first went to uni. We both slept with other people
During that time so whilst I don't like the thought of her with another guy I accept and understand it, but... We have recently gotten back together and there is a an issue I am struggling with and need some advice on. One of the guys she slept with is on her uni course and sits with her group of people she sits with in lectures so she sees him quite regularly, another guy who she just fooled about with no sex works at the shop she works at at uni so she sees him quite regularly, and the second guy she slept with works at the store she works at when she comes home from uni so she sees him then. Am I right to not be happy about this and is it too intrusive for me to say I would be more comfortable if she deleted their numbers and deleted them from Facebook? I feel mean asking it but I want there to be some separation between what happened in the last year and our lives now. I feel like its only fair considering I don't see or speak to the people I slept with to ask her to get a degree of distance from them. What would you advise? Thank you in advance.