I've always been of a mind that someone becomes a "failure" when they stop trying to succeed, not when they their efforts don't pan out. Since Edward has always kept trying, I wouldn't say he's a failure at all.
He has a tough hand to play. In the royal world, he's "ordinary" in many ways -- he's never been dashing figure, he's not a war hero, he's not the heir, etc. He just seems like a nice-looking guy who takes on relatively low-profile, day-to-day royal tasks without a lot of fanfare. That's dutiful and admirable.
But, in the "ordinary" world, he'll always be a little different because he's a royal. No matter how much he strives to live like "the rest of us," he's always going to be a person who attracts attention and stands apart. When he goes to a concert or the library, he's a royal acting like a normal person, not a normal person. The very fact that we know he does these things and there are Internet discussions about whether he "lives a normal life" is proof that he isn't normal.
I think he manages to balance the two aspects of his life pretty gracefully. It must take a lot of courage to stick your neck out and try something like starting a company or getting into an elite military unit when you know the world is watching, so I give him a lot of credit for that.