Why do I feel crazy in relationships?

I was obsessed with my boyfriend. I stalked his location all day long, angering myself if i noticed he left his house so i’d question him where he was and who he was with. I would cry and rage when we interacted with females (friends, family, strangers). Even if he met male friends i’d get angry. Only i should’ve made him happy. I had photo albums of just him that i would stare at for hours, admiring him. I was so obsessed. I needed to just inject him into me and take his soul into mine. I started thousands of arguments through my jealousy. I tried to control everything he did, where he went, who he went with etc. I would fantasise about him morning till night, then dream about him. I wanted to lock him away forever and keep him with only me and only interact with me. I don’t want to see him happy if it’s not with me, i’d rather him die than move on. I would need to text him every second of the day, or i’d cry and think he hates me. I stalked every social media he had-analysing it thoroughly. I used to sit in my room, crying, starving myself, hurting myself over things that happened between me and him. Tiny things. After we broke up, i made 23 different phone numbers, messages 6 of his friends, made 3 instagram accounts and tiktok and sent over 200 messages in a day just to see a reply from him. I hated how he had a life around me, i wanted him to myself. Just me and him. No interactions with anyone else. MY boyfriend. I relied on him for everything, and i expected it back. I used to shout and cry over tiny things that i would make up in my head and pretend he actually did it but he didn’t. I’d tell him to leave me and never come back then argue if he listened.
Why do I feel crazy in relationships?
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