I'm sorry to hear of your loss. The only female friends I can say I have had my whole life are my sisters. I do not do understand women in some ways. I was always a tomboy when younger and in high school, those I was around were always back stabbing their so-called friends. You are lucky to have had a friendship such as that. I know you must miss her deeply.
As for your new realtionship with Fred, I can see the natural progression of that considering it was something that seemed to be on the table for years. I hope all goes well for you.
I wondered...do the three of you live together or still maintain the two households?