The speaker is talking to someone who came into their life, made it warmer and better, and then walked away. The complaint is simple and raw: you can't give me all this and then take yourself back. The repeated "you can't" gives the poem the feel of a plea dressed up as a rule, as if the speaker hopes that saying it firmly enough might make the other person return.
What stands out is how tender the memories are. Smiles, butterfly kisses, a gentle hand on the back are small, quiet gestures, and the speaker treats them as life-altering. That shows how much the speaker leaned on this person. The last line drops the anger and admits the real problem: "i can't handle this new life without your guidance."
The mood is hurt, vulnerable, and a little desperate. The short, plain lines and lowercase "i" make it sound like someone speaking in a raw moment, not trying to sound polished. It's less about blame than about feeling stranded after being changed.