Am I pushing too hard?

I hear you. My DD also has severe problems with the "I can't"s. We push her to do things that we know that she CAN do (often to the tune of huge tantrums), and then afterwards we talk about how great she did, how we knew she could do it, etc. Then the next time she says "I can't", we remind her that she indeed can, because she's a smart girl and she needs to use her 'I can brain' rather than her 'I can't brain' and that when she said "I can't" the last time, she could (remember when you said you couldn't ride a bike? You did, didn't you? And now it's easy!). We also remind her that Mama and Daddy will NEVER ask her to do something that she can't do. (She has attachment issues as well.) And part of the process is teaching her to use coping skills when she's feeling anxious. Though we do have to be careful of those, because she'd rather spend 3 hours in her room, saying "I need to go to my room to calm down" than do a task that takes 3 minutes and is moderately difficult. We have found that if we don't push our DD, then she will do NOTHING for herself. We need to push her on some things and usually are pushing her on 1-2 things for a given time period, until she masters one of those things, then we add on a new one. It's a balancing act, for sure. You know your child best.