Families & Friends Of Addicts Support Group
Addiction affects more than just the individual. This community is dedicated to the families and friends of individuals suffering from any form of addiction. Mental health professionals are increasingly considering alcoholism and addiction as diseases that flourish in and are enabled by family systems. Family members react to the addicted person with particular behavioral...

So sorry for what you are dealing with. You will find support here, it's truly a great group of caring people.
Like Kim, my addict is my son. But there are others here who are dealing with spouses or boyfriends/girlfriends who are addicts. Either way, you can vent away and find comfort and support from people who do understand how you feel.
Please do not believe your dad and husband are using substances because of you...that is definitely not how it works. It is not your fault in any way, and you have no control over what they do.
I will also repeat what you will hear a lot from this group, please make sure you and your children are safe, first and foremost.
Welcome to our group. I agree this is a wonderful group that has been a lifeline.
I have a few observations.
I'm having a hard time understanding a crack addict that only uses once a month for 11 years or more. He almost certainly is using crack consistently, probably every day, and simply letting it get out of hand about once a month while he "disappears". Also, drug abuse, particularly with something as addictive as crack, is going to get worse as time goes on. This is likely to lead to financial, legal and health problems, if it has not already. You need to protect yourself and your children from the fallout.
If you want to see where a crack addiction can lead, I recommend the book Portrait of an Addict as a Young Man. It's an amazing story of a young man on a 30 day crack binge. I don't know how this man survived, but he did and he's sober now.
Crack is a very expensive drug. It is very common for addicts to commit crimes to get the money or, at least, to do things like running up credit card debt taking cash advances. If you are married to him, you could be on the hook for his debt. You may want to request a credit report to see if there's debt out there you don't know about. Check any joint savings accounts you may have together that he may be wiping out.
Your therapist is absolutely correct. The stress of "dealing with you" is not pushing him out the door. Addicts are very good at making us feel guilty and blaming us for their problems. He has been using crack for 11 years, probably longer. He will use with or without you. It doesn't matter what you do. The pull of the drug is too strong.
You were raised by an alcoholic father, so you are used to living with addicts. That is probably the cause of your anxiety and panic attacks. I think that if you were to detach from the addicts in your life and focus on yourself and your children, while keeping up therapy, you will someday find your anxiety and panic attacks will disappear.
Another observation is that you don't mention anything about your husband wanting to overcome his crack addiction. That's a key point. He seems to think that it's acceptable as long as he's a "good" husband and father when he's with you. Meanwhile, he's risking his health and your financial security, as well as risking jail or prison. He may be driving while high, perhaps with you and the kids in the car with him. If you can't live with him continuing to use crack, then you need to set a boundary. What are you willing to live with? Are you willing to stay married to him if this continues? Or do you require that he get treatment to stop the drug? (He will not be able to do it on his own.) Decide what your bottom line is, communicate it clearly, and then don't back down.
The other thing to consider is that addiction has a strong genetic component. You clearly have addiction in your family with your father and sisters. Your kids have your family's genes and your husband's. They are at risk of becoming addicts themselves. If they are in an environment where their father is openly using crack (they will figure it out) and their mother is putting up with it, they are much more likely to use drugs themselves and become addicted. If nothing else, they will be set up for the types of anxiety and panic attacks that you have experienced from the stress of living with an addict father. I hope you find the strength to do what is best for yourself and your children.
You are clearly a strong person for overcoming the background that you came from and staying sober yourself. I'll keep you and your kids in my prayers. Please keep coming to our site to let us know how you are all doing.