Relationships

Is my girlfriend doing something behind my back?

My girlfriend of 4 years has had a long time guy friend. We live together. They dated for a week in highschool, and hooked up a couple times later. While not together mind you. I've known and briefly talked to him over the course of our relationship, but he's never hung out, and we've never sat in the same space before. Until almost a couple weeks ago. After I asked if she was cheating. He hates me because she fell for me after telling him he's next. That's it. Knows only of me though her. She always pushes our relationship down with him. I've told her I don't like this. I have had a constant "bad feeling" when she suddenly started spending a lot of time over there. Always late by her own time frame. The guy got a car. I would play games with her, spend entire days, outside on a porch talking with her. She still felt this way. Then she bought me Horizon:ZD. She started a big fight over her insicuritys. Spent 2 day going over, staying late, then she'd come home she'd be ready for bed. He'd come by every evening, and she'd hang on the phone for him. I've had a bad feeling since. He's been pulling moves like spending money on her. Taking her out to eat. Trying to take her to a gun range. Tired to take her out of town to get his kid. She was out late, texting me she can't come home because she and her friend drank. But the DD is just fine. At the time she was supposed to come home, she asked for two more hours. Goes offline for those, then suddenly texts on the dot of her new time. Then shows up home in 10 mins from a 20-25 min drive. "I didn't see him speed" She has told me she wanted me to go inside while he's and his buddy are here. Then told me after some pressing and bringing it up later, that he asked her to, and so did his buddy. When I tell her I'm not comfortable with something, it's called bitching. I'm told I hurt her feelings. When we "talked", I told her how I felt, and her response was agresive, defensive, and ended with nothing.
Is my girlfriend doing something behind my back?
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