Listen, get out of this mind set. I felt I was the invisible one in the group. All my friends always had attention and lads after them, whilst I was just their friend and saw nothing more of me.
Weird though, since I've been with my boyfriend I noticed boys were with my friends for all the wrong reasons, my boyfriend pointed it out and I was shocked. Those boys were with them because they pretty much gave 'it' away for free. And quiet unnoticed girls are the ones lads look for, as they're innocent and don't put it about.
Please don't fret about this, just make yourself feel good and the right guy will come along soon enough.