Most Helpful Girl
This whole thing here, dear, is Sounding more and more like A... Train Wreck.
Get off her Caboose and Move on Off of this Track that will only End up a Disaster, which I am sure with 'It all turned sour grapes and now I fill ripped half," it May have already Began to Go... Bad.
I realize you are in love with her, and she May be having Marital issues that have caused her own Heart to go into Over Drive.
However, he IS your cousin and this is a Married woman. Remember, Blood is Thicker than water.
Move on now. Lick your own War Wounds, and When you are this Ready Eddy again, go out into the World while there is still One, and find the Perfect Girl and Give her a Whirl.
I don't think neither if you do not Agree that there would Never be Any other in this Lifetime, I Believe, Once you Leave, that perhaps In your Wildest Dreams, she is Out There Somewhere.