You have every right to feel angry. It is one of the major points in grief. It comes out of no where and it comes in full force. With that said I have also felt angry and I have come to realize, from the advice of a friend (non-BLM) that anger is fear.
What is your fear? I think once you get to the core of that you will be able to understand when you get fits of anger. I felt so much anger at those family members who chose to walk away from me when I was at my worst. My fear was, being alone in this darkness. I have accepted the fact that I may not have those around me that I was expecting, but I am so grateful for all the BLMs and friends IRL (in real life) that have been there for me too. I felt angry at all the other people that were in our 'friends' circle for getting their babies, while I did everything right. My fear was, that even though they know I had a baby, that they would not look at me as a mother. I was/am angry at my body. I tested positive for MTHFR and I have a fear that my body will not be able to bring home a living child for me and my husband.
I get SO angry sometimes (even with all the knowledge I have on anger) about people complaining about 'stupid problems' as you put it. With this I do not think it is fear. I think we just want others to realize that there are such small things in life that used to bother us, but we have been dealt the WORST hand (in my opinion) and it is really important for us to feel like others know 'we had a real problem'. What i can tell you is that my therapist told me that I should respect the fact that 'outsiders' are entitled to their anger and complaints as well. But I disagree. I would prefer if they left their petty problems out of my life while I am grieving. So for those people around you that are being insensitive I would suggest, taking it with a grain of salt. Listen to what they are saying and that is it. Do not give 'your two cents' because you will only be added to your anger. I wish people would see our situations and sit back and think "Wow I am complaining about this, when it is a fixable problem and poor Stephanie just lost her baby." THAT would be in a perfect world, and in my perfect world babies don't die, so we would not need to even discuss them.
Hope I was able to help.
But hey, its just "My Two Cents"