dont understand her

ok, i'm dating one of my bestfriends and it's the most serious relationship I've ever been in, and hoepfully if everything goes fine in 4 years we'll get married. It's amazing how we both have the same ideologies and beliefs regarding everything, there isn't even one topic we can disagree upon and that's why we thought to give it a shot and see what happnes, but at the sametime, sometimes I feel as if I don't mean anything to her, as if I'm just a friend, she always says how she likes me alot (we dont use the word love since both of us dont believe in it) but I feel like I'm just one of her guy friends, nothing special, and it drives me crazy.
For example, one day I was in a really bad mood and I didn't feel like talking about what was bothering me, but I told her it's not you which is true. And she knows that I'll eventually tell her but I like my privacy, she seemed livid at the end of the night but the next day when I asked why was she like that, she says as usual nothing's wrong, and for two hours straight we're having a conversation and our best friend who happens to be a guy is with us along with her sister, and most of the time she's talking she's looking at him and only him. I told before that you should look at everyone sitting and not alienate everyone else. I'm not asking for her to look at me the whole time but still specially after I was in a bad mood the day before and she knows I'm still in a bad mood she should try not to alienate me atleast. Then my best friend leaves, and she looks at me and starts conversating. WHAT DOES THIS MEAN?!!!!!
I'm not asking her to be with me 24/7 to make me feel special on the contrary, she should go out with her friends away from, but I feel like I'm being alienated whenever our friends are with us, specially it they're guys. I'm not jealous or anything like that, but I don't like the idea of being alienated. Mainly I hate the way she jokes around with guys, she jokes with them as if it's me, well that's fine but it makes me feel like any other guy except for the sex part.
She understands me perfectly but she still does stupid things that she knows I don't like and keeps repeating them. WHY!!!!!!! What can she do to make me believe how much she likes me?
Am I having two much expectations from her? Tweet