Tarev, it's just tough luck!
Don't feel sorry, just try different ones.
I've also killed a few Adeniums, struggled with a Faucaria ... parts rotted, and then the rest was all covered in spidermites and then I just threw it away... not worth the trouble.
I got two really tiny seedlings of Orthophytum gurkenii that are sooo tiny after a year or so, that I can only sprinkle water over them (I am afraid to uproot them if I water them properly).
And the list could go on...
