Tweetu need to relax bro... i know ur doing all this cuz ur afraid of losing her, yet by doing all this ur causing her to become distant... ur being too pushy... to agressive... i mean just imagine someone telling u what u can and can't do.. how would u react... she needs to have her free space too... if she didn't like u she wouldn't be with u right now... so relax man. let her go to that party or whatever... she'll like u more for being reasonable... and understandable... the more u keep pushing and telling her what to do, the more ur gonna push her away...
ur just doing bad to urself (not eating etc) and her..... let her do her thing... ur not her parent... u can suggest sometihng to her, but not tell her to do it... noone likes that...
so relax... make up for it tomorrow by taking her out for a dinner or so... and tell her she can go to the thing...