Im confused about my ex?

So me and my ex broke up 3 months ago. We tried to be friends and it was working out for a while but sometimes when we saw each other she was treating me rudely. Whenever she was in a bad mood, I tried to help her out and ask what's wrong but she would just blow me off. So I was just like "whatever if she doesn't want my help I won't ask ill just leave her alone". But whenever I was in a bad mood she'd ask me what's wrong. Sometimes I'd tell her what's wrong but sometimes I just didn't feel like telling her. So whenever she was in a bad mood I'd try to help her out and whenever I was in a bad mood she'd try to help me out. But last week, she caught me in a really bad mood and she asked me what's wrong. I told her "that my manager was being a *****" then she was like"dude you just cussed" and I was like "and your point is". Then she said to me "wtf your problem I'm just trying to help you and you act like this" so she starts freakin out . then we got into a huge fight and she says were not friends. I tried apologizing but she said apologys don't cut it for her so then I'm like ok whatever. So basically my question is: why did she freak out when I said your point is? And why does she like to help me out when I have problems but when she has problems she doesn't need my help? Anyone know