see someone else said this was minor stuff, to me these things are a big deal.
Its called being reliable.
1) return the call,if nothing else call the person back and tell them you have not forgot and will get back to them soon.
2) I don't understand really, was help not needed and dude got stuck at the last min, or was he being lazy and then at the last moment thought he would have everyone else do it.
The later should be a hanging offense (j/k but it is pretty bad)
3) don't stand people up,if you don't want to date the person or something better comes up,you may be the asshole of the hour but tell the person whats on your mind,don't leave them wondering.
4) why was friend not invited,and think about if the friend is not welcome where you go and to tromp in the same circles you do then why is that person your friend?
I have very few friends,but the ones I do are real "friends" more family than friends if I am welcome they are and vice versa. if the person is not welcome then they are more an acquaintance than a friend.
5) if this is one the the above mentioned "real friends" and you cant take the time out to show up at his party,or at least call him and make an excuse so that they are not waiting on you,what kind of person are you?
unreliable,untrustworthy,and you need to check where your loyalties lie and maybe stick with that instead of having people assume you are loyal to them and come to find out you are not.
these are my solutions,very easy to do basically do what you say and say what you do.
and dwarf,I charge a lot for my services as well, more than what I think is fair.
but look at it this way you have a special talent that they want to exploit, its a talent that a lot of people have and if they went to you it has to be for something,so the people are happy paying what you are charging.
if they are happy and you are happy then its a win win.