For context and the original reply (e.g., without spelling and grammar corrections), see the original reply on Reddit.
Keep in mind that either there were no local Jewish cemeteries in some communities or your ancestors for whatever reason either married outside of the traditional Jewish faith or were converted to Christianity—whether willingly or forcibly. Anusim v’bnei Anusim Ashkenazim (Ashkenazi Crypto Jews and descendents thereof) get overlooked a lot, mainly because many of us ended up believing (and still believe) in Jesus and/or otherwise did (and/or do) not fit the mold of what Anusim are apparently supposed to be: Sephardi, secretly Rabbinically Jewish (Both secret Karaites and Jesus-believing Anusim get overlooked.), not mixed blooded (or if we are, straight-down-matrilineally Jewish), and willing to reconvert to traditional (i.e., Rabbinical) Judaism if we end up finding out that we’re Jewish.
Just because some people (perhaps even within your own family) when to tell you that you’re not Jewish just because you’re not religiously Rabbinically Jewish, that does not mean that you are not Jewish. I have had the same problem with people trying to tell me that my ethnicity is contingent on my religion and my blood purity (it is sickening; and I have had people tell me that because I did not get the luck of getting known autosomal JewishDNA according to some websites, I am apparently not Jewish.). Don’t let the limpiezistas (blood purists) and others get to rob you of your heritage.
PS This also applies in regards to the racist activist group at one university—“limpieza de sangre” and inquisitions of any kind have no place in any decent society.