I can understand your concerns as that is totally valid. Trauma has a way of limiting the choices we make in our lives, because we want to be kept safe. A counselor would help, as well as understanding more your own intuition vs. fear and making a decision from that place.
I can tell you my story. It might help or not help put your mind at ease. I can relate because I have a very similar fear due to bleeding out right after giving birth to my first (and only). She is so important to me that I hesitate in getting pregnant again for fear I won't make it through the next one. So I get what you are going through, even if I can't understand what it must have been like to grow up without a mother. I am so sorry for that.
It would be important to do some digging around the medical history aspect. One other thing - did either your mother or grandmother have particularly long or particularly fast labors? Both situations can increase chances of hemorrhage. Length of labor can be somewhat genetic only b/c of body/pelvic shape. You just want to be prepared with as much information as possible.
In my case, they never figured out why the hemorrhage occurred. No genetic diseases, nothing. My great grandmother passed giving birth to my grandmother but other than that, no family history of hemorrhage. I was healthy, 31 years old, low-risk pregnancy, eating well, passed the gestational diabetes test, etc. I suspect it may have been due to the fact that my labor was pretty quick but again - they didn't have any answers. I also gave birth at home with a midwife, so when I started bleeding she did give me the recommended medications, which did not stop it.
But you can plan for it by choosing a great hospital that's on the cutting edge of technology. There are so many life-saving procedures now that bleeding out (especially from a natural birth, with no induction, and no c-section) is not as big of a thing. I was VERY fortunate because the doctors used a procedure called Uterine Artery Embolization to stop the bleeding in my case which saved my life (and my uterus!). It is also very important for you to take good care of yourself, listen to your body, etc. I believe that if I had taken a nap during early labor instead of going grocery shopping and making dinner, things may have ended differently (I'm serious!).
There are also herbs you can take during pregnancy and acupuncture can help prepare your body for birth. I believe all these factors combined allowed me to survive despite the fact that I did suffer a class 4 hemorrhage.
My point is - we don't know for sure if that will happen to you. But if you find a great doctor and hospital, you should be able to prepare yourself for the possibility given your family history.