I come and go on these forums but for a few months I've considered posting something pretty similar as I've found myself wondering about my purpose. Which, I think, is superficially pretty weird, I'm 32, I'm genuinely happy, I'm married nearly 7 years now to a beautiful woman whom I love and continue to be attracted to, we have an incredible daughter and another little one on the way, while I'm back full-time in medical school. I should be too happy (and honestly way too busy) to be having any sort of personal existential crisis. However, I've been in the same boat, feeling uncertain of the direction I need to go and absorbing the associated frustration.
A lot of it for me has been around the impending decision of having to choose a medical specialty to which I will essentially be committed for the rest of my life. I've found myself being pulled in innumerable directions as the competitive part of me wants to step up and go into the most highly selective field I can get into, while the father and husband in me wants to ensure that I'm choosing a field that will allow me to spend quality time with my family on my terms, while the narcissist in me is pulling to something high profile where I can "prove" to others of my superior intellect and ability (I say that cynically though I certainly can't avoid feeling it at times).
I share my own story for a couple of reasons --- 1) to point out that kids aren't the answer either way, I love my daughter in a completely inexplicable way, and she provides such a sense of fulfillment and joy in me (not to mention frustration and pain) on a daily basis, but just because you are a parent doesn't mean that you are and only ever will be a parent. Just like you probably felt before you got married how weird it would be once you were married, then you got married and realized you were still the same person you always were, having kids doesn't really change that. Priorities change, certainly, but you are still you. B) I'm realizing that patience is a key player in all of this. When you are younger, there is constantly something on the horizon, whether it's going to high school, losing your virginity, getting drunk for the first time, moving out, going to college, graduating college, getting your first job, buying your first car or house, etc. Whatever it is, it's really just around the corner, and even though you are always antsy to get to the next stage, you are never antsy for too long. Suddenly though, all of those big life moments are behind you and yet here you are getting antsy again, yet there's nothing around the corner like you've become accustomed to. So you just continue to be antsy, waiting, and waiting, and waiting. This is probably the point where many people start to feel confused and lost. And you are faced with the question "what now?" I'm beginning to believe that the answer here is patience. You've got your life together, things are going well, you're in a good situation, so just be patient. You don't have to force the next big step in your life upon yourself prematurely. Relax a bit, recognize where you are at this moment in your life, and ride the wave a little while.
So my advice, start checking off items on your list, but do it stress-free. It's not a race, just dive in and start doing what you can to enjoy and accomplish them for yourself (not for your facebook updates or for us), as you work your way through those items bigger goals will start to congeal in your mind in due time.