drew10, women look at things in a totally different perspective than us men ... often more logically, as a matter of fact. Your lady is more inclined to respect her marriage vows than you, and because of that, you should be grateful. Cuckolding (or even swinging) makes absolutely no sense to most married women, and certainly racial cuckolding is simply too radical for most. As my favorite Star Trek character, Spock, use to say ... "Your desire is not logical" . I imagine you'll have a lot of issues to address and bridges to cross before getting her to agree to racial cuckolding simply for your entertainment. Its almost for sure, though, once you turn her on to cuckolding, she's probably going to be just as difficult to turn off. That said, it helps if you know what her sexual fantasies are ... not yours, but her's. That's the ground floor you're going to have to start from before getting her to come to your level.
I encourage you to read the short book by John Gray called "Men Are From Mars, Women Are From Venus" ... its a psychological approach to why/how men and women approach issues and resolve problems so differently. Its been out for years, but still a very popular paperback. You can read an outline of the book on the internet; it should entice you to want to know more about what makes the ladies, and men,"tick". I believe both of you would enjoy it. You'll probably see yourself in this book.
Particularly in today's world, women aren't the submissive creatures of the old days; they have wants and needs, and if their men aren't providing them, they're less likely to tolerate a lazy man in bed and quicker to look elsewhere.