Sorry, aspie or not, your girlfriend comes across as a total user. From what you've written above, it seems like she blows you off to do her own thing/see her own friends constantly, and expects you to bend over and state how much you love her, without reciprocating. You may be taking things a bit seriously, but only because the relationship's so unbalanced.
Ok, you can learn to understand her and help her and be kind yadiyadiya... what's she doing for you? How is she trying to accomodate your needs? Do you really want to put up with emotional neglect your entire life? You sound like you've pretty low self-esteem, and she's just dragging you down further. Even if it's not deliberate, she's not giving you the support you need. Basically, if you give 100%, expect 100% back. Not 50%.