Some Some break-ups are amicable and others are so nass-teey. Some
people stay friends after a breakup, and others want to forget they
ever knew each other's name. Then there are exes that say you are
going to remain friends, but then they start acting really cold and
She sees you and quickly walks away or ignores you altogether, or she talks to you (even sometimes initiates the conversation) only to start telling you how great her life is, now that you are not together. She goes out of her way to be affectionate and flirtatious with other men when you are around and tells you about this or that great person she's seeing. She even talks about her (great) sex life and what this or that other guy does with him. And whatever you say or do, all your best intentions are met with hostility, suspicion, resentment, irritation, anger, vindictiveness and worse.
Why would someone who said she loved you now be hurting you intentionally?
Some exes act mean because they really want you gone. It's a passive aggressive behaviour where someone feels that if they are mean, cold and cruel to you, you'll get the message and leave them alone. This is especially the case if the person feels that you are in denial or are not accepting the fact that it is indeed over. You trying to hang on to her or be a part of her life irritates her. Your hanging around irritates an ex even more if you are still professing your undying love and commitment.
Why doesn't she just tell you to get lost instead of intentionally trying to hurt you?
If the break-up was not nasty or if she broke up with you, she may be struggling with a combination of pity and guilt. She feels pity for you because you are a really "good" human being but she just doesn't have those romantic or love feelings for you anymore. She feels guilty that she can not love you as you love her and that in some ways makes her a "bad" person. The combination of pity and guilt gets under her skin, literally, making her angry at you for making her feel this way. Your sad puppy-face doesn't help.
Could it be that she still has feelings for you?
It is possible that your ex is not over caring for you. Her cold, mean and cruel behaviour isher way of trying to deal with the feelings she still has but does not want to feel. You can usually tell an ex is dealing with conflicted feelings by how they go back and forth. One day they are so loving and kind and the next mean and cruel. Their reaction to you reflects what they feel at that time or on that day.
But if the person is angry, mean and cruel to you all the time, with no "loving and caring" breaks in between, they want you gone, like really gone!
Just a word of caution. The sweet-and-mean intervals may also be a result of Bipolar Disorder. If your ex has a history of Bipolar, it may just be that they can't help themselves.
Does s/he have to hate you that much and be so cruel?
A majority of relationships where an ex acts cruelly post-break-up were toxic to begin with. It's rare for a healthy relationship to go toxic and unhealthy post-break-up. For some exes, it's a power/control thing. If they can control how you feel, they control you. For others, they interpret your pain as "you still care for him/her" and that makes them feel good in a twisted way.
If this is what is happening to you, and you are still trying to get your ex back, you need to ask yourself, "Is this person treating me with love and respect?", "Is this the kind of woman I want to spend the rest of my life with?", "What kind of life would that be?"
Should I then leave my ex alone and move on?
It depends. If this is your ex just being her usual mean and cruel self, it may be best for your own good to move away from the emotional abuse. But if your ex is a kind and caring person who would never act mean or cruel unless forced to, then you need to look at yourself. May be your refusal to accept reality or your needy and clingy actions are forcing your ex to try to push you away. Work on changing you, and see if she starts warming up to you again.
Sometimes it's her, but sometimes it's really you.