The only thing that worries me about you not being out to your family is that when they do find out (and they will), you'll not only have to deal with their reaction to you liking men, but also their feelings about not having been told X years ago. It could complicate things. I know one person who came out to everybody but his parents and extended family, and an aunt caused hell when she found his myspace page. She, of course, called his parents to report to them rather than calling him.
OTOH, you know the situation better than I do. Just go into it with the understanding that eventually it will come out, whether it's next week or 20 years from now.
I have to say, one of the benefits of my coming out so relatively late (at 34) is that I wasn't concerned at all about what my parents' extended families thought. As you get older, they'll become less and less important in your world. My suggestion is that you forget about what they think about you and deal with what YOU think about you.
P.S. Now's a good time to take the word "lifestyle" out of your vocabulary.