SAHM with an MBA

For those of you who don't know me personally - I am 30 years, married and have two daughters. I am an SAHM - stay at home mom. For awhile I was a WAHM - work at home mom, but I didn't like what I was doing so I closed the business. Before I had children I would have described myself as a woman with an MBA specializing in marketing, a BA in English Lit and Middle Eastern History, and a certified ESL teacher. Before going to university, I would have described myself as an new immigrant to Israel who served in the IDF. So to sum this up, I am a female expatriot living in Israel with two daughters, a husband and an MBA :-) .
The MBA seems kind of out of place in the list, no? I also don't know what I make of my education. Sometimes, I look back and think I am lucky to have finished a second degree - to have this on my resume. More often, though, I look back and say, "What was I thinking?" Did I not know I would end up spending years at home with my children, in which case I wasted precious time and money sitting through boring classes in business structures and accounting. I could have spent that time learning what I love. I guess it doesn't really matter now - the MBA is mine while the time no longer is. I am trying to look at the years ahead of me with more direction, with more of an understanding that I need to have a goal as to what sort of life I want to lead and according to that, make career (and not career-related) decisions.
So what do I want to be when I grow up? Oh, I am grown-up. What do I want to be today/ tomorrow/ in five-ten-twenty years? I don't know. This not knowing is leaving me feeling empty, lost. How can I be 30 years old, with two kids and an MBA and have no idea what type of life I want to lead?