First off my housemate and I are good friends, but shes very emotionally immature and needy. I'm usually fine with that because I'm busy enough she can't monopolize my time and belongings. But she is very much one of those people who are very controlling and moody behind closed doors but who are seen as sweet and innocent outside.
So far this week she has complained that I have my PS4 in my room and she can't watch DVD's in the lounge because she doesn't want to pay for a DVD player. Fair enough but I like gaming in my room and I want to use my things how I want to use them. That I don't bake for her when I refused to let her eat an entire batch of cookies because I'd baked them for a specific event. She'd already eaten seven or so. That I'm not being fair when I won't let her help herself to my food in the fridge because it looks nice because it's expensive. That tonight I've baked a cake and won't let her cut into it the second it's out the oven and she'll have to wait until tomorrow when I've iced it because I've friends coming over for coffee and board games. That I won't leave my room unlocked so she can borrow my things at will, I'm a private person and I have no desire to allow people access to my room when I'm not around.
She has also told me that if I go on holiday with mutual friends without her she'll never forgive me. Sure it would be a shitty thing to exclude someone from something they'd enjoy but if she can't take time off or afford it the rest of us are still going to go. Plus if it's something she won't enjoy I really don't see how there is any issue whatsoever. I know I personally would not care.
She can be hard work but she can be equally good fun and I get through these issues by reminding myself that she's naturally a jealous person and has her own issues that say more about her than they do me. Plus this time next year I won't be living with her. Plus I'm sure that others may find living with me equally difficult, albeit for different reasons.