Nigerian Married Men And Adultery With Young Ladies

I just had to post this because i've had enough. Im 22 years old and have been bombarded by Nigerian men who are married. The worst so far happened at a Nigerian Independence Day party out here in L.A. where i was stalked by this married man. This is not the first time that this has happened to me and a lot of my friends go through this as well. Recently a friend was called all night by a man that was doing business with her company. She had to call her phone company to change her phone number because he left threatening messages saying that he will come after her if she doesnt mess with him. 
Back to my case, this man told me that he and his wife was at the parade earlier and he had seen me and he was so excited to see me again. I told him i dont date married men or men with girlfriends and he told me it wouldnt be a problem he can hide it from his wife well. The thing is that he wasnt the first guy that is married to hit on me that day. I've been through the same thing at other nigerian parties.
Why is it that Nigerian men are so unfaithful, im so mad that i dont even want to marry one because im scared i will be in the place of the wives on day. I dont dress provocatively, im more on the conservative side but like a normal 22 year college student would dress. I hate to say it but i think people accept this behavior in our community because its so common.

Ok i think i should have made this more clear in the topic at first. I dont date Black guys(African American and West Indies) because they are for the most part cheating or players or psychos and the few that are good are already taken. Now the reason i chose Nigerian men is because in the States Nigerians put themselves on a pedestole compared to akatas (Whites and African Americans). We think that we are well behaved and can do no wrong. They say oh we dont have as much divorce but then at all these places they are hitting on young girls to mess with on their wives. I dont mind being approached by Nigerian guys around my age or at least single but married one? come on? A lot of these guys got young kids and a beautiful wife at home. Im sure that those guys would leave their wives if they find out that they were messing with younger guys or any other guy for that matter. Why cant we do better?