Is There A Way To Make Flowey Like you?
Solution 1:
You've obviously already read some spoilers, but I'm not sure exactly what you do and don't know, so I'll be using spoiler markup anyway.
First, a direct answer to your question with the bare minimum of spoilers possible:
If you do the True Pacifist route, then Flowey will be sincerely nice to you, and wish that you were his friend. This requires you to go through the entire game without killing any monster at all (0 EXP earned, LV 1), and also requires you to befriend several monsters along the way. If you are missing another aspect of the route, Flowey would normally give you a hint about it after the credits (he has already given you the "don't kill anyone" hint, and he's not going to repeat himself). However, killing Asgore causes him to yell at you for that instead, even though it's after the point of no return and therefore not strictly relevant.
Now for the spoiler you probably don't want to read unless you already know everything about the game:
Flowey is really the last remnants of Asriel Dreemurr. He is generally unable to feel positive emotions, and as a result, he will never truly be friends with the protagonist, or with any other character, unless he's returned to his original form. This only happens in the True Pacifist ending, and only temporarily.