If you are 100% P&T for 1 condition, and that condition is for a mental health issue, you will not be able to work or attend voc rehab. Is this true?
No, that isn't true.
The veteran who is rated as 100% P & T on the schedule of rating disabilities (a schedular rating) is allowed to work as he or she is able. That's whether the rating is for a mental health issue or not.
The veteran who is rated as 100% P & T due to unemployability (A TDIU rating) is only allowed marginal work or that work that earns less than the federal poverty level.
Most agree that productive work is a great therapy in and of itself. Go for it if you're able.