Islam marriage does he love one more than the other?

My friend is married 2 a muslim man which she became muslim also over the years. He married another woman in his country which he is only legally married to the one in his country,he has been with my friend 10yrs and the other 7yrs. My friend does everything for him she cooks, cleans, takes care of there kids, works for him but when he talks to her about his other wife you can just see how happy he is when he talks about her. He even made my friend feel that she is nothing told her she was no good and the other wife was better and talked to her about there sex told my friend she wasn't good in bed and the other wife was now I know women in them countries don't do a lot of things in bed like an american women can do so why does he put her down and make her feel bad when the other wife he only see's every 2yrs? She told me he is getting better and not really talking about the other wife but he still has that glow on his face if any one talks about the other wife, I feel so bad for my friend I feel like he just uses her and takes advantage of her, and the other wife is his favorite when she can't do anything for him she's all the way in his country can some one explain this 2 me? I wish my friend would just leave him oh and one more thing he doesn't even want kids with her he said it's to hard here in america but in his country it's easy to take care of the kids there, I don't get this low life person who wants kids with the other lady that's why I don't like him at all!