My boyfriend told me a story about something like this that happened to him, a long time ago. He had been dating this one girl, I'll call her Jane. He went away to college, and she got tired of the long distance relationship and started seeing someone I'll call Tom. When my boyfriend graduated, he came back to his hometown and rented a house with Jane's brother and Tom.
My boyfriend started seeing a different girl, I'll call her Susan. Meanwhile, Jane was dating Tom. She eventually moved in with Tom.
Susan became jealous and suspicious because my boyfriend's ex, Jane, was basically sharing a house with him, even though Jane was now dating Tom. Susan kept accusing him of cheating on her with Jane. The relationship finally ended, because she just couldn't believe that my boyfriend was being faithful to her while his ex was living in the same house. My boyfriend was deeply hurt by Susan's lack of trust, but could do nothing to assure her that all was well. To be honest, if it were me, I would be very uncomfortable if I knew an ex girlfriend was living in the same house as my current boyfriend. Hope this helps!
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Dreams are renewable. No matter what our age or condition, there are still untapped possibilities within us and new beauty waiting to be born.
-- Dr. Dale Turner