I agree that normal can be found...you're already well on your way to it. You were thrown a heck of a curve ball in life with the loss of your husband and you did what you did...can't undo it. But recognizing it all, and not repeating it, is how you can make it better.
You are realizing the hurt you inadvertently put everyone (including yourself) through while you were trying to cope. So, OK, you didn't make the best decisions in some regards but none of what you did is so damaging it can't be reversed.
You are rebuilding a relationship with 3 children that you will ALWAYS share with your husband, no matter what, and their love will help you. You are going to have another blessing in your life that you will love and cherish, even if how that child got here isn't under your now ideal circumstances.
I think just getting back on an acceptable emotional track will help everyone, including your father. I am so sorry for what you are going through but you're certainly not too late to make amends! I wish you all the best as you work toward your new normal.