YOU SAID:
i went to my boyfriends house this weekend
INTO JAPANESE
私は今週末、彼氏の家に行きました
BACK INTO ENGLISH
I went to boyfriend's house this weekend
INTO JAPANESE
私はこの週末彼氏の家に行きました
BACK INTO ENGLISH
I went to boyfriend's house this weekend
That didn't even make that much sense in English.