Hi Lacey,
First let me welcome you to the recovery forums. It's a great place to get the help you need and start to heal. I know it's very hard to watch a loved one abuse drugs and alcohol without being able to help them. Thankfully, there are the Alanon and Naranon programs and they are geared specifically for the people who are close to the addict, family members, spouses, etc.
There are a great deal of mothers dealing with the very same issues you describe on these boards in the Alanon and Naranon forums. There are posts labeled Sticky on the top of the forums. These are very informative and answer some of your questions.
I would suggest posting on those boards as well,as there are so many people in your predicament willing to offer guidance and support. It is possible to get your post moved if you don't want to have to write it over again. I would be happy to have the appropriate person do that for you.