a question for the over-achiever, perfectionist types

My whole life (okay, maybe not WHOLE... but at least since high school) I've preferred to be busy. I'm a multi-tasker-perfectionist with an uncanny ability to procrastinate. Those may seem like contradicting forces... and, well, they really are.
But that's proven helpful to me over the years - staying busy keeps me from procrastinating too much because I have to get my butt in gear if I want to get things done. And the Perfectionist-Over-Achiever-Katie definitely wants to get things done. And Procrastinator-Katie keeps me from killing myself with doing too much at once.
Here's my current dilemma (I alluded to this in my last post):
I was always a pretty busy gal. In high school, it was dance, NHS, musicals & plays, tennis, youth group, work, and the other standard teenage-girl pursuits of shopping and talking on the phone. Undergrad had me in some clubs (on the E-Board of one), pursuing 2 degrees at once, being an RA in the residence halls, belonging to a home group in my church, and other standard college-girl pursuits such as shopping and talking on the phone. By grad school I was married, juggling classes and my job as an assistant hall director in the residence halls, and after grad school I was working full-time, taking care of our new house and leading (with my husband) for YoungLife/WYLdLife in our area (and still shopping and talking on the phone occasionally). I've always had a full calendar. Until now.
Mark is still a YL leader. Any of you who have been in almost any type of ministry (but especially those with kids, I think) know that you always feel like you could/should be doing more. His schedule in the fall will include regular meetings at least 3 nights a week, along with appearances at sporting events and fun, spontaneous social activities with our high school friends. On top of work.
Here's my problem: Although I often felt completely inadequate and out-of-my-element as a YL leader, I love the kids I've gotten to know (girls I've known since they were in 6th grade are now in driver's training, heading into 10th grade - eek!). I miss seeing them regularly. I loved the toughness of the job, and the incredible harvest I reaped when I did not let myself grow weary of doing good. I was serving Christ in a real, tangible, sacrificial way.
I don't lead anymore. I stopped about two months before Hazel was born because I knew it would be too much for me. I wanted to focus on my family... but....I am having the darndest time shaking the feeling that I should be doing more. That I should be the SuperMama who is knee-deep in some kind of ministry and has a perfect house and is out and about and doing things. I've struggled with this kind of feeling before, and I really don't think it's from God. I think Satan is able to pinpoint my weaknesses and use them in such sneaky ways... I wind up feeling so defeated.
Being a stay-at-home-mama is so much more than I ever thought it would be. It is so much cooler, so much harder, so much more fun, so much more boring, so much more challenging... so much more. I know this job is important. I want to do it - and I know how blessed am I to be able to do it.
I guess my question is... how do you know when to let yourself "just" (haha) be Mama? And how do you do that?? Don't get me wrong - I like keeping my house organized, providing a clean & pretty home for my family, cooking, baking... it's all good. I know it's valuable. I'm just not used to having that be my focus. Why does my brain keep telling me that it's not enough to do those things?
I don't know how much sense this post is making... but any input, advice or encouragement you could provide is welcome, friends.