It means a lot to me that you came to my place. 你能来我这儿对我很重要。
I don't know what to say. That means a lot to me. 真不知道该说些什么,这对我很重要。
That means nothing to me. 这对我没有意义。
It doesn't mean anything to me. I don't care. 这对我一点意义都没有,我才不管。
Happy birthday sweetheart. I love you. 亲爱的,生日快乐,我爱你。
It means a lot to spend the day with you. 生日当天能和你一起过对我很重要。