Got myself in a bit of a sticky situation

Hi there everyone, I was wondering if anyone could help me. Basically, I have this friend who we should call A, who don't get me wrong, I love to death. I have known her basically all of my life (we went to Primary school together) but we have only really got close in the last couple of years. I would describe her as lovely, but also very, very controlling, and she get's stressed out and jealous unbelievably easily. Back in December, she asked me to go on holiday with her in the Easter/summer. (I've already been on holiday with her once in the July previous, and had had an awful time because of how she babied me and got annoyed at the slightest little thing). If I'm honest, I didn't want to go on holiday with her again, and so I told her that I didn't have enough money (even though I probably would have had) and with uni, finding the time to go away is difficult. I know this makes me sound so incredibly fake and like such a bad friend, but I didn't want to ruin our friendship either by calling her out on her behaviour! So instead I chose to lie, and I'm incredibly ashamed of that. Anyway, at Uni my flatmates and I really want to go away together as I won't ever be living with them,or probably seeing them, ever again. In fact, we've already booked to go on holiday in about 2 weeks time. This is all fine, but I tell A everything, and I haven't told her that I'm going on holiday yet, because I know that when I do (or she'll see on social media) she'll flip out. She's evidently pull the 'why is it okay to go away with them and not with me? why are you prioritising them etc? you're such a fake friend' card, and I honestly don't know what to do to make her react better. I know I should tell her the truth but I honestly don't think I can make myself do that because of how she'll react. I feel like I'm constantly walking on eggshells around her! Do you guys think I'm in the wrong? Or do you think she's overreacting? How do you think I should approach the subject? Thank you so much for your help everyone! Xxx