I agree that the best thing to do is to talk to her about your worries. Getting her to talk about any suicidal feelings is really important. I would also check on how well she is able to care for her son right now when she is so depressed. Children pick up on a lot more than people think. (this comes from a person raised by a depressed mum)

Another thing to consider is this - HIPPA does not allow her therapist or Pdoc to talk to you, but it does not prevent them from listening. You can call both, and express your concern at your daughters condition. They may not be aware of how depressed she is, and that her significant other is big stressor. They may also not know that both of them have dorked up appointments lately.

You are a good mom to worry. Just be sure to take care of yourself too! Remember to do what you can, then step back to do some self care. Sort of reach out, then step back and nurture yourself. You can't constantly take care of others, you need to take care of you too!! Emmy