Was my cousin wrong?

I posted a while back and people told me to mind my business lol I mean she’s my cousin and I wanted to be honest with her.

My cousin has only been in this state for 3 years and in that short of time she got with a married man.. that man has been married for 20+ years and that’s not the worst part she became good friends with the wife before getting with the lady’s husband. And its been now a year and he divorced his wife for my 19 year old cousin. This man must be in his early 40’s. He bought her a house and a $600 puppy plus a car. I don’t think she did this money more cause she was lonely and her parents basically left her once she turned 18. I’ve tried to tell her this is wrong but she told me they’re truly in love and later blocked me. I feel bad for this women because I see her around and she tries so hard to fake her happiness but cmon 20 years?? I know she’s hurt! And I feel so bad for her. Is this really true love? They claim to love each other and that he lost feelings for his now ex wife years ago