Hi Lindee,
I know how you feel. My ex-wife has custody of my son for the same reasons. I have visitation any time I want, but I have moved out of the area and back in with my parrents to try to get straight. I've been clean 3 months, actually 3 months today!!
My son is 4 and it's hard not to be able to see him grow up. I hope to move back to the area when I feel like I'm in a little more control of my life. Sometimes it's harder when you are straight because you can look at the mess you've made with a clear head and it really looks *ucked up! But at least I'm not continuing to make things worse. I agree that if you are clean for a year now, you might want to look into getting some kind of visitation. Your kids probably don't understand why you don't see them, they just know that Daddy doesn't come to see them. Maybe you've tried that route allready. Anyway, congrats on your clean time, if you stay clean there is always the possibility that you can rebuild some kind of relationship in the future. Keep strong on what I'm sure is a tough day.
Peace,
Tyler