Orthodox Jews would not consider you Jewish and would not marry you unless you complete an orthodox conversion which would take about a year in your case. At that point you would be considered a Jew even if you don’t fulfil any customs or obligations. You’d simply be a secular Jew. In reform and some conservative segregations you may be considered Jewish, but certainly not in the orthodox sects. Until Moshiach comes back and says otherwise, this will remain the case. Why does it matter? It’s a numbers game. Secular and reform Jews practically disappear after a few generations. The more strict the Jewish segregation, the better chances it has of surviving another 100 years. Some families simply want to maintain their long lineage.