When things become muddied in relationships it is sometimes best to step away from the drama and view the participants and what each party wants and gives. Alot of peple get confused between attention, drama and love. Hence I suppose our craving for TV soaps.
If a relationship is based around disharmony and arguments, and this is not suitable it might be better to spend some time apart.
My thoughts are work to separation based upon trial and timetable. (If this suits).
Alot of long term relationships are based upon sufferance, thankfully you have become aware and can set an example to your son based upon honesty, strength and reason.