Granadella, welcome to Mumsnet!! 😂
I'm going to annoy them all now by apologising for all the smug, superior, ungenerous and judgemental comments. There are some people on here who just mouth off and attack others who've come on and been honest and asked for advice and support. You're quite right - that's not what the site is supposed to be for.
Consider yourself as having landed in Mad Max world and been attacked by crazy psycho hyenas and I've just driven up beside you in a mad machine and given you a hand up.☺️
Firstly: so well done for every single moment you've been clean. Every minute is another achievement and a step away from all the rubbish behind you. Beating an addiction is an immense personal challenge and you are nailing it, so WELL DONE. You're on a good road now. Feel good. Be happy.
Next: it's a great road, because it will eventually mean you can be the best dad you really are for your children. What you're doing now is, more than anything, a gift to them. You're going to give them yourself, a proper dad.
To understand: this is all going to take time. Every moment down your road, you're rebuilding yourself and your credit with others. That's another big achievement. And a hopeful journey. But you've got, by the sounds of it, quite a bit to make up for.
Your partner has made her decision I would think as much to protect the kids as for herself or anything else. She may even, somewhere deep inside, have also realised it was the only way to help you.
My advice is:
Don't expect anything from her. You effectively messed up her life, her kids' lives and her family by not being able to cope, by the addiction, unfortunately (another good reason to have kicked that shxt). You have most likely fxxxed it up with her for at least the foreseeable future, and maybe permanently. BUT you are co-parents. You are not going out of each other's lives.
So: accept the effect of how you were (I think I know this and have). Don't expect anything. Work on your freedom from that past, and enjoy being yourself again. Get strong. For your kids.
Put the relationship with your partner on hold for now in your mind, and concentrate on getting solidly better and good for your kids. They need you. (Not you chemically altered - just pure you)
You are obviously going to have to keep on diligently and hope that in time (and plan for it to take a long time), you will be given a hearing. Don't expect a chance at a relationship for now. Work on deserving a chance to be normally in your children's lives.
She's had to be both parents. You've really put her in a situation where she couldn't rely on you at all, and she finally realised it would be a lot easier without you. You have to earn the trust back. I think you get that.
Ask nothing. Do your job of getting stronger every moment. Be there for your kids. Get ready for the day when she finally begins at least to see you as someone who is taking this seriously. And never let them down again. It's not an option. You know that, too.