Re: Need advice from anyone who's willing to give it...
You can be angry with him anytime you want, just don't attack him personally. Make him feel guilty for hurting your feelings. But don't run him down. If you don't keep a good line of communication with him about all things you will drift apart.
I might give you a possible explantion for the specific instance you gave.
He might have really wanted to stay in for a number of reasons. But..then his buddy comes by and grabs him up and takes him out with him to drink or talk or whatever. He might not give much resistance or the reasons he wanted to stay in would be something he would not want to tell his buddy. Men are funny like that..If he did'nt feel too good, he might have not told his friend because he did'nt want to look like a wossie. Or, his buddy had a problem and needed someone to talk to, or one of several reasons that had nothing to do with him putting his buddy over you. But...I can tell you one sure way to screw up a relationship. Try and come between friends..male or female, you or him.
Being SO's does not give anyone EXCLUSIVE rights to the others time. He needs to do what he needs to do and so do you. Trust and understanding is something that you develop over time.