Hi! It's not an easy question.
I know it seems that "te" means "you" before a verb, but it's not exactly like that:
Example:
"Te amo (a ti) = Tú eres amado/amada por mí" (In this case I do the action "I love" and you just receive the action "you're loved")
It happens the same in English:
I love her, she is great.
I love you, you are great.
So, in the last sentence you use "you" twice but they don't mean the same. You can see this in the other sentence because you use "her" (le/a ella) and "she" (ella)
Examples:
"I told her to come."
"Le dije que viniera. (a ella)"
"I told you to come"
"Te dije que vinieras"
"She is my sister"
"Ella es mi hermana"
"Tú eres mi amigo"
"You are my friend"
When we say "Te gusta", "te" is no refering to you but what you like.
"Tú gustas" could be said, but it'd mean literally "you're liked" so "People like you", it would mean you're nice or attractive and people like you in general.
I hope the explanation is not too long and difficult and it helps.
^_^