Finding my purpose in life

I am sitting in front of my computer with hubby away with the boys and baby girl sleeping. Now that its quiet, I can think and hear what my thoughts are saying. I've come to realize that I have been paying too much attention to others and not my self. I realize I am too focused on my children, I care for them daily but am wrapped up into there world same goes for my marriage. I have lost interest in my hobbies/passions and really don't know what I like to do, could be because I don't know what to do when I do have the free time (sometimes). Things that I have loved doing is non existent in my life now. I don't have a job or career and if I had to go back to school, I wouldn't know what to do? Wow what happen to me? Every now and then I would get sad and down and out and couldn't figure out why, but I'm starting to think its probably because I don't have a passion/goal/hobby. My hubby has his hobbies which includes diving and surfing. When I see him happy and excited cause he caught a "huge" wave or a "monster" fish, I start to think like "wow I want to feel the excitement he feels!" The only question now is how do I do that? They say when you are happy as a person, then everything in your life falls into place and all areas- family, marriage etc. will be happy. So I guess what I'm trying to say in this post is do what you have to do to make yourself happy, dream big and reach your goals, find things you enjoy doing and do them because in the end your spouse and family will thank you.