How Long Should Medication For Bipolar Disorder Be Taken?

Hello my name is Daniel and would like to ask ... if a person had been taking bipolar medication is it possible that they can be taken out of it ? I got married to my wife in 2011 and was told by her father in-law a year later after meeting him that his daughter was bi-polar and that I needed to get her help immediately before she got worst . I had asked my wife if she needed to tell me about this situation she mentioned that she was on medication but later was taken off the medicine for bi polar ??? I see cases where she lashes out at me and pulls a 360 where I m thinking where did this come from , Just things she says that don t make any sense at all ... Also takes the truth and manipulates the wording to make it into her favor by throwing in little lie and making it true . She gets depressed and is extreme doing projects around the house and leaving them half way ..Please get back to me I would like for her to get evaluated but she gets offensive and wants me to go it and get evaluated as well . In other words in order for her to do this these are her conditions and I don t understand why she wouldn t want the help ?