just stay at there house

You invite them over to your house and then in the actions bar a invite to stay might pop
up or your sim might bore the other sim out in which case no

Not only that but, your husband/wife will be living in your house, their house turns into
"empty house" i checked and it's full of furniture, but no one goes there. I like kicking
their bins over though, no one's there to get annoyed.

You can't move into your spouse's house,but what you can do is to get him into your
house.

If you are figuring out how,firstly,you call him on the phone,then you invite him over on
a reasonable time for your spouse to come over,say... Idk... 8.00-19.00? Thats the time
for me. So just invite him over,talk to him and there should be an option saying : ask to
move in.
Click on that and if he agrees,you will have a new roommate ; your husband!
Hope this helped!
Source:i am also a sims 3 ambitions player. :d