Big Bear, wanting what you want in a relationship is not to much to ask for.
Smoking pot has always made me more affectionate. I have witnessed the same response from others. but I have noticed the isolation affect with other drugs. SO.... I don't know if I think that was this girls problem.
Anyone that tells you they do not want to show their emotions, in my opinion has issues.
And affection is great although you said you are sometimes overly affectionate. Just remember there is a time and place.
Personally I think you made the right decision. I think it is normal to feel sad after a breakup and so you wonder if you did the right thing. Give it a while, stay busy. Say hi if you see her and work and keep it quick and light.
Good luck to you