Widows & Widowers Support Group
This community is dedicated to those who have lost a husband, wife, or partner. Anything is open for discussion here, with the hope that we can focus on grief, bereavement, life after loss, and continuing on after a great loss.

Is there anyway possible to find out who's the beneficiary? Hopefully it's not her.
If you are not the beneficiary or are, the will say something to the effect that it can or cannot be transferred. They may even ask if you know the whereabouts of so and so.
You also have an option of filing as executor of estate. It won't change the beneficiary, but in that role you can add it to estate and access who recipient is.
This is a lot to handle but usually the filing as executor is easy enough if his will doesn't preclude you.
You may be able to get a temporary death certificate...this is one that will help with getting paperwork started and may be amended later by officials, as long as there are no circumstance that are in question. It cost me $20. per copy after funeral in my state, but they waived the cost of copies I needed more than the first one.
In your last sentence, you mention the feeling of guilt, and this is what caught my attention.
I can tell from what you tell that you've already made an impressive effort to be friendly to the step-daughter and others of your dear husband's extended family. And this accomplishes two things: Clearly they are the ones closing you out, and it lets you know that you were once serious about getting along in this particular situation, only it is not favorable for you . In my personal opinion, you will soon get over feeling guilt as soon as all is settled and closed with your husband's estate.
I'm happy that you are careful to think of what is most important now. And I hope that you don't spend a great deal of money to straighten everything out. Yet to be honest, I would feel the same about the step-daughter receiving an inheritance under the circumstances of her thoughtless ways. Then she really is a victim as well, because she appears to have been very young and raised by troubled adults. Perhaps, if you think of her as an innocent and immature child, it may better help you to accept that she may be entitled to getting a check from your husband's IRA. You may also consider that your husband is at rest with the idea as well. For surely he is in a safer place now and away from this crisis, in which case he would surely want for you to keep your conscience secure and uncluttered as well.
Hoping for your best,
Remiah
And I admire how much you treasure the love of your husband. I feel that he has a good soul too. And he rest in peace for this reason. One day, as she matures, his daughter will think of both of you and it is likely possible that she will desire to seek for you; this is possible with the passing of time. At which course of time your thoughtful counsel and personal forgiveness will be of great value to her and also an inspiration to her. I do believe that the leading voice to bring on her humility will be that of her caring father's. The voice by which he always wanted to comfort her with is now much stronger in full force, in spirit, he still raises her.
Your love with your husband is so sacred. And I thank you for sharing this heartfelt writing. All will be well. You are so good and very strong, Anita. God bless!