I think you're letting your obsessiveness and insecurity color your beliefs about what other people should and shouldn't do.
I disagree that it's "disrespectful" for someone to ever contact their ex again.
You're making up reasons (ex-girlfriend) for your boyfriend's lack of affection. Instead, look at the REAL issue - Your relationship is not really a happy one for you. Why are you making up reasons for it? if your boyfriend was still in love with his ex, which really seems like a long shot, then what can you possibly do about it? You can't change his feelings. By going through his Email every day and becoming jealous and making yourself crazy, you're only hurting yourself. You're not helping the relationship you're in and you're not going to create positive change by acting this way.
I wonder if you've ever told him how you feel. Does he know you want to hear that he loves you? Does he know the feelings you have about his ex? Does he know you're unhappy with the amount of affection and intimacy between you?
It sounds like he cares about you but this really doesn't seem like a relationship that can make you happy the way it is. If you're not prone to a lot of jealousy in general, you should really consider moving on from a relationship that definitely isn't bringing out the best in you.
Your problems with the intimacy level of this relationship aren't new.
It sounds like maybe you have a lot of anxiety coming from how he acts with you in this relationship.
I think that you are hugely confusing things here. This is not all about your emotions but is about seeing reality and dealing effectively with reality.
All just my opinion, but no, taking you to a family wedding does not mean anything about his feelings for you one way or the other.
I have lived in the state of anxiety that you are living in now.