The term "SO" (my SO, etc.) gets used a lot on this forum and it's a bit confusing at times. We all know what the term "wife" or "Husband" means, but "SO"?
OK, it stands for "Significant Other" but it's a bit evasive. How significant? Have you been living together as husband and wife but just never married? Are you living together at all and if so, is this planned on being permanent? Are you just using the term for your current girl friend or boyfriend?
And is your SO the opposite sex or the same sex as you (a gay relationship)?
Not that I care how other people live, but it's hard to give good answers to questions when we don't understand the relationship.