You wouldn't be over the top AT ALL for making a change and going back to work.
Being a SAHM is a little risky (IMO) for a woman in a stable, happy-enough marriage. Even if you have a great H, he could die, become disabled and unable to work, get laid off, etc. etc.
But addiction is a huge deal in a marriage and we all know addiction is progressive. Even if his current attempt at recovery sticks, relapse is always possible and you'll always have nagging doubts somewhere in the back of your mind.
Most married couples (even parents) are two-career families. If that is so stressful it derails his recovery, he wasn't that serious to begin with.
If you get back into the working world, even part time, I highly doubt you'll ever regret it. You will be protecting yourself and your children if/when things take a bad turn.