Arguments between husband and wife

My question is based on my situation below, is our marriage still valid? My husband and I have had a argument back in november 2014 and since then we have not been under the same roof. We have communicated over the phone and twice in the presence of others, but overall every conversation we had was with a lot of argument, fight, negativity in all forms, no matter how hard I tried to make it positive. We have not had a happy conversation ever since on good terms as a genuine husband and wife would in a normal non-stressful life. What concerns me that with all that negativity and separation going on, is our nikaah still valid? Are we considered a married couple? I hope I provided enough information for you to analyze the correct Islamic way for my situation.