I was confused because you said you would leave, but it's your house.

It sounds to me like you've been detoxing in the bedroom and the kids are upset because they're bored. Maybe they're worried about you, too. But, if they are acting like they 'hate' you, it's probably just because they feel neglected and are bored.

So, I think just make more effort to play with them. Take them to the park, to a movie, if you can. There really isn't any need to say anything.

If they ask about your health, just saying your doctor gave you medicine that made you feel worse and you had to go off it if good enough.

Their mother is a drug addict. I think you should try to show them you are strong and there for them. If they have a 'step-mom' who is also having issues with drugs... That's got to make a big impact on them. I'd try to get drugs out of the picture in front of them- they see more than you think they see.