I(23m) have been in a relationship with my gf(24) for 2 years now and it has been hell, but I'm not able to end the relationship.

I'll be honest with you: she's a really good girl, and she love me desperately, but I can't stand this situation: I can't do anything, if I do something without her she's crying raging and complaining, if I do a bad joke she's upset for hours, she's moody as hell, possessive, and always brings problems! One day she's lazy and she complains with me that she doesn't want to study, the next day is stressed, the day after that she has something else. She always cry for everything leaving me feeling like a piece of shit. She's manipulative. I'm leaving hell, I'm always sick, I can not concentrate on anything because of her interruptions every 5 min. BUT I wasn't able to leave her, and I don't know why! Tried a couple of times during several of ours weekly fights over something I Did wrong. But I've always never said:"it's over". I can't because I feel like a piece of shit because I always said that I love her just to keep her for destroying my days...(my fault I know). Now I'm thinking seriously about leaving her after our uni exams, but i fear that I will not be able to. I need your help, I need a new way of looking at things that will enable me to find the strength to make unbelievably sad and, the thing I fear the most, to give explanations to questions like: -why all of a sudden this? Why you didn't tell me that I'm doing something wrong. -why you told me that one day we would be married.... Please I'm begging you, give me some advice because if I'm not ending this in the next months I'm considering suicide: this "relationship" robbed me of everything I've had. I hate her, but I'm forced to say I love you, just because we are quarantined at my parents house. Note: maybe she will go to her parents during the summer, but I don't know if I'll have the strength to leave her while she's away like that. I feel like I don't have the strength to do anything

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