:hug:sending you a welcome hug,this is such a tragic loss.
Grief is not something that has degrees of "right" too clearly you were very close friends.families and friends gather strength from each other.It is very early days and a difficult time with xmas coming up -but no time is not difficult.Grief isnt a quick journey more of a nightmare rollercoaster, and a time when we fear for all our loved ones more yet perhaps also a time when we take stock of their value too us and maybe change our prioroties in a positive way too.In time sharing your happy memorys will be one way in which you can help her children and continue to be an important part of their lives.But in thes early days just getting through the next hour and the next day is as far ahead as we can look.
I doubt there is a single person on this site who hasnt at some time blamed themselves and felt guilty in some way -there are always those what if questions that plague us -maybe f we had said or done something different this wouldnt have happened.It is part of grief to feel like this as is the anger.
Without knowing your friend its difficult to say -but if you had phoned, would you have known she was unwell, would she have told you, - perhaps she had no pre - warning of this herself,and felt fine when she went for her bath.
None of us are professionals here but all of us are at different stages of grief, so do understand where perhaps those who havnt find it difficult too.Keep coming and keep talking it does help.