Hi SilentTears, You have been through so much and for that I am so sorry. I cant help but think that there is a reason that your not being silent here...your reaching out, for help.
Your right that not all children are pulled from their homes due to drugs and abuse issues. It is a sad set of circumstances that you and your family have been through.
I cant help but think that what you need to do is get to your local hospital. If you are having active sucidial thoughts then you need to be evaluated by a professional doctor...yes, a psychiatrist. Most likely inpatient hospitalization so that you can get on some medication and be supervised properly on that medication for the first little while. This may not be what you want to do...but it can make all the differance in you quality of life and the deepness of the depression your going through.
I dont think you want to harm yourself and something is holding you back as your posting here hoping to find that answer or inspiration to keep going.
Your husband wouldnt want you to give up...neither would your children..regardless or their circumstances (I am sure they think of you and love you). We dont want you to give up.
I am going to post some links for you and I want you to use them...just pick up the phone and call that is all you have to do. Please just do that...
http://suicidehotlines.com/
http://suicidal.com/depressionandsuicide/
http://suicide.com/suicidecrisiscenter/