You sound just like my mum :). She has ADHD, depression, bi-polar type 2, among other things. Despite all of that, she is an EXCELLENT mother. In her worst states she has asked me if she is a good enough enough mother, and I have never hesitated to say yes. I think that being a good mother that cares too much is MUCH better than having a bad mother that doesn't care! Downside is, my brother and I have inherited most of her problems.
I think the main thing you need to do is get treatment. If you aren't on medications yet, get on them. I know the media and certain communities say drugs are bad, among other things, but if you really do have an illness, you need them. I know they worked wonders in my family.
The bonus with dealing with your illness now is that if your children start having symptoms (I was in my teens, my brother was in primary school when we started presenting if you're interested) you'll be more informed on how to help them. I saw my whole family go through psychiatrists and medications before I did, so I wasn't concerned or scared at all.