Feeling extremely sad about giving cat back for adoption

On Jan 1 I got him, he's been rejected by multiple people who took him and rejected idk why he has this fate despite being healthy and good. He would cry whenever he'd sense I'll leave him too. He'd watch me sleep, he'd watch me work, hoping I keep him, i just couldn't give him time to play whenever he'd cry...i realized I'm not capable of keeping and I'm too alone rn...i would fail to sleep, I wud fail to isolate myself to be depressed and suicidal so I let him go ....i'm really not sure he would find his forever home....seven days of keeping him has fucked me up emotionally. Can't keep him, really can't let him go. Really can't take care of him but try, but trying isn't enough when there's hope he can find someone better but I don't have any at the same time...please help me 😞