Sorry to make you not feel special :P
Well honestly, that is really good sign, that it seems her obsession over your activities is not straight out control, but rather jealousy and boredom (which sounds kind of crazy), but it is kind of fixable. Its not a character thing, necessarily, if she were only busier, she wouldn't be so demanding of your time.
I would first, bring it up to her, that you would like to see her enjoy herself more, and do things just for her. If she does, do something, ask her about how it went, how she is doing at it, be it Yoga or self defense or something. This will show you are interested in what she is doing, but she owns that activity so its hers. I mean, some people are rather "dependent" by nature and women in general are more likely to have that tendency. In my experience, all you can do is try your best to encourage her independence, because once she realizes that your relationship may get stronger, if you were more independent, she could embrace it.
I am by nature an independent person. I don't wait around for people to "do something with me" I just do it, and enjoy what I want to do. But honestly think that is a pretty rare independence and confidence, for a woman to have, so its a matter of encouraging that in your wife, and explaining how difficult it is to be told you can't do what you love to do, and how you really enjoy having your own hobby and time to yourself.
Bottom line though, you should NEVER feel bad for taking a reasonable amount of time for yourself, everyday, with kids that time could reasonably shrink. But no person should make you feel bad for taking care of yourself and doing activities you like to do.