Am I wrong to be uncomfortable with my wife’s relationship with her cousin

Since last year i married my wife, it has been my cousin this, my cousin that.
She and that her cousin love themselves too much. The guy comes to our place almost every two weeks and he always pass the night.
Anytime he comes around, my wife will lose control.

They chat everyday and night on WhatsApp.

I complained to her parents, they told me just to ignore them, that their closeness started from their childhood. People call them twins and they look alike truly.

Yesterday, i closed my shop and drove straight to my wife’s shop to pick her as usual, so we can go home together. When i got there, i met her shop locked. I called her on phone, she told me that she’s already at home, that Chizzy, her cousin came.

I got angry, when i got home, she opened the gate for me, hugged me and went back to the parlour where her cousin is sitting. She lied down and placed her head on his laps as they continue gisting and laughing. I managed to control myself without complaining. The guy left this morning.

Am no longer comfortable with their closeness. It’s too much.

Please i need advice on how to handle this.