Call your therapist today, and ask for an emergency appointment. Even if you don't think it will help, do it anyway.
Perhaps this is also the time to have the hard conversation about approaching your doctor or a prescribing psychotherapist regarding medication. But do give yourself a week; anniversaries of a death can be very, very hard, especially the first few years. If you are still dragging next week, please consider that this may be grief complicated with depression, and then you need to seriously consider your options of how to go forward in a healthy way which will strengthen both you and your family.
Having had multiple miscarriages myself, for tomorrow: do something meaningful to help you release some of those feelings of anger, disappointment-- at one point, I wrote one of the babies I lost a letter, and then let it go on the current of the river. It was a freeing moment. Miscarriages and stillbirths are horrible things to live through, and it's not surprising that a lot of pain is coming up for you, which suggests to me that your 'shutting down' is about self-protection. You don't want to hurt any more, and feeling hurts. I was fortunate to have a lot of support during my last miscarriage and really needed it; it was also good for my husband that we had a counselor who could see his pain and his perspectives too.
A counselor can help. Medication can take the edge off- temporarily or for a while, while you work through finding some resolution and peace. I will also say this as lovingly as I can: you do have a lot of goodness in your life, too. Try to keep things as balanced as you can (I know it's hard) and please reach out for help.