I think I can answer this question since I have first hand knowledge. Trying to learn a new language from your spouse or live in does not work. However having a native speaker to correct your grammar and verbal communication really helps. In the house you have to decide what language you want to communicate with as the primary. In our situation it was English and I took Japanese in college. Here in Japan we still speak English in the house with a lot more Japanese being added everyday as my language skill gets better. I do believe you need basic language course to start with and living together communication will be everything, so pick a primary language to communicate with and build from there. Also I have set aside a time in the morning and evening to study I have found learning to write kanji and hiragana are required as you learn to speak Japanese. For me I have also learned writing in kanji and hiragana has helped me retain words better.