<human>: Can you succinctly summarize the text in 1-3 sentences?

My boyfriend's worked at this retail store for about 5 months, and now his ex-girlfriend got hired there. She's been working there for two weeks and I don't like her, I'd really rather he not work with her. Do you think it's unreasonable for me to tell him to quit? It's just retail and he could probably easily get another job. When he told me she works there now I said something along the lines of, "Oh okay, that's greaat" I wasn't totally rude about it but I'm sure he gets the idea that I'm not happy about it. I haven't told him that I want him to quit yet, but I'm thinking about how I could do it without seeming controlling? any suggestions? Do you think I'm justified to feel this way?
<bot>: My boyfriend of 1 year and some change, works at a retail store and now his ex-girlfriend works there too. I want him to quit.