Why does my girlfriend hate me all of a sudden?

There will always be issues in a relationship, maybe she felt like you have done something purposely or you don’t show attention to her as much as you did. Ups and downs are normal in relationships but the smart thing to do is know how to deal with them and not overreact.

maybe its something you said or did. Let her know you love her and care and find out why shes mad at you

Who knows? Sometimes talking about it with her doesn't help either. All I can say is seek help from your support network or from a professional

Your girlfriend might not hate you, but reflect on anything you might've done that could've hurt her feelings in the past. Were you ignorant towards her when she was trying to express her feelings? Did you say something hurtful towards her? There must be a reason.

Hate is a strong word, perhaps see it as annoyance first and then move on from there. If she is your girlfriend then you must have done something serious to incite hate from her, think back on all your interactions with her within the past few days. Move from there and you may find the answer is simpler than you think.

No one can answer this question but her. She must have a reason for giving you the cold shoulder and you won't find out unless you sit down and talk to her (calmly).

Maybe she discovered something about you. Maybe somebody told her something about you that it's not true, or maybe she is having a bad time.

Sometimes it's not that easy. Partners may feel that their significant other is showing more anger specifically towards them when in fact they may be upset with themselves. I personally get extremely angry towards my boyfriend of 5yrs when things are bombarding my mind. I see it as venting where as he sees it as this mean spit-fire coming at him. I would say, sit down and try to talk about it. See what is going on in both party's worlds.

Well maybe considering sitting down with her and talking about what’s wrong and see if u can work it out

This is something that cannot be answered unless she is the one to provide you with that answer. Ask her about it, don't stop after 'are you mad at me?'. You can always say that it feels to you that she hates you and that it makes you feel a certain way, that you want to clear the air and that you want to know what's bothering her.