My son's stepfather wants to adopt them both and I'm not interested.

I have two sons that I haven't seen in three years. I don't make a lot of money and I'm putting my current wife through graduate school. They live 2 1/2 hours away and their mother won't help me at all, won't bring them to me or anything. I pay child support every single month without fail and have for the last decade. I talk to my oldest on Facebook and when he's not cussing me out and then telling me he's sorry, he's threatening me with various things. This morning he decided to tell me that his stepfather wants to adopt him and if I don't "perk up" then his mother will have my parental rights terminated. I told my son a long time ago that I won't have much money and I probably won't be able to see him until September of this year when my wife starts working and things are better on us. Then I want to see them all the time. But my question is can they terminate my parental rights? I pay child support and I do the best I can right now with the hand I've been dealt to be involved in their lives. My youngest won't talk to me and my oldest will talk to me, usually to tell me how much he hates me, or how much he loves me depending on what day it is.