Well it was he who waked outside and didnt bother his arse about me thats the point .It was rude
However, when you meet up with a gang of people you can get distracted or just lost in the conversation.
Perhaps it was thoughtless of him not to come back in for you, but hardly the end of the world.
If my fella did what yours had done, I would have gotten up and just followed him out if I was uncomfortable sitting where I was.
The fact that you are so upset about this one incident would suggest you might be a tad on the sensitive side?
It might be thoughtless of him to behave as he did, but it's hardly something to finish a relationship over.
With regards to him talking down to you, how do you approach him when you are discussing it.
Do you say "you do x, y & z to me" (accusing)
do you say "When you say x, y & z to me it really hurts my feelings and makes me feel like you actually don't care about me" (showing how his words effect)
If you are both together five years then you care for each other.
I believe you should both have a calm, frank discussion on what you both want from the relationship and whither you care enough for each other to improve how you both communicate.
Long term relationship of any kind require constant work.
Otherwise, you take each other for granted.
Best of luck.