Be cautious about giving out advice that can totally ruin somebody’s life, and for someone someone you don’t know. For you it’s an easy “good luck, God bless,” but it’s her very life. Divorce is also a very grave matter and should only be undertaken if truly necessary.
That might or might not be the case here. We don’t have all the facts, nor are we entitled to the facts. Even if you yourself have experience with this type of cross, that doesn’t mean that the same thing will happen here.
I’ve dealt with drug addicts and alcoholics, and they can be extremely challenging. I agree they won’t get better without them deciding to change - but even if the addict won’t change that doesn’t mean that divorce is necessarily required.
I’ve also been through a divorce. It’s horrible. That means the OP is between a rock and a hard place. I have the deepest sympathy for her, as I’m sure we all do.
The OP should weigh her serious maritial obligations and vows with her responsibility to her children against the possibility that continuing to live with her husband will result in serious harm to her and her children. She should seek in-depth counseling from an orthodox priest and a professional Catholic counselor before making such a weighty decision.
We should also pray that her husband will convert and seek professional help for his addictions.