she's my first girlfriend and i've always said i'd treat a girlfriend with respect and put her first all the time, and for the first few weeks i did. but.. turns out it ain't that easy, and now i find myself sometimes going days without talking to her, and putting friends before her a lotta times. and the worse part is, after we had been going out for about a month, this other girl i secretly had a thing for broke up with her boyfriend and now things have been getting kinda flirty between us, even though i don't plan to do anything.. i dunno what happened but it looks like i became the asshole boyfriend i said i'd never be. no one been through anything similar?
If, on the other hand, you are just being lazy and you DO want to talk to her and spend time with her then you just need to put a little effort in. You don't have to totally abandon your friends to spend every waking minute with her, just spend a descent amount of time with her, and a descent amount of time with your friends too.
But it sound to me that you just aren't right for each other if you only feel like your SHOULD spend time with her rather than really really WANTING to spend time with her. Relationships are about caring about each other and having fun, not feeling obliged to behave a certain way towards somebody if you just aren't that into them.