我爱他，他不爱我用英语说

I love him, but he doesn't love me.
He said I was too young. he said he would wait till I grew up.
He said he would never lie to me.

I love him, he does not love me
He say me to be too getting little, wait for that I grow up
He says he will never deceive me

同意举人的直译。
而意译则更简单了：“I'm a sucker."
呵呵，搞笑而已，别介意。
Just kidding, no offence.