Jason,
It is not important what others think or say about what you did or did not do. In your own words you stated you and your friend admitted each knew what was going on and in the end realized the relationship was premature, if not impossible. Of most importance is you and she amicably reconciled your relationship, and that is the good part of the experience, the ability to separate the real from the desired and remain friends.
Others here, myself included, have or desire to reach out beyond our grief for 'normality'. As some posted here about your connection to another woman, there was caution. Perhaps their insight was from their own experiences with a relationship with the opposite sex.
Whether it is grief from a death, or divorce, or whatever causes us pain, we desire to escape from that pain. It is a normal human response.
The fact that you took steps to reach out, found it for awhile, then realized where the other person was was not where you were, shows you care, not that you mislead.
There will be more occurrences like this in the months ahead as there were in your past. Acceptance, rejection, misunderstandings in forming a new relationship are just part of the process, a part that we conveniently forget.
I am looking forward to the time I can take those same 'dangerous' steps as I did in my youth and as I did when I first met my wife. To not step out of my comfort zone (yes, even grief can be a comfort zone) is to accept emptiness and loneliness as happiness based on memories, rather then developing new experiences which leads to new, and hopefully happy new memories.
In my life, as in my wife's life, we often reflected or related to our life's experience. That included discussing our previous spouses. To ignore the time we spent with these other people in our lives would have been to ignore a part of us.
As I move forward, there will be a time when the memories of my wife will no longer hurt to the point I stop looking for new companionship and for the happiness and sorrow that endeavor can bring. To not reach out only means I will never find it and life will be so much less then what it can and should be.
Just my two cents from a guy who has had a bad couple of days to the point I could not do much about anything.