Not all old family stories are pleasant. Bigamy is one of those things that most people want not to mention. If it exists in any part of your family, you should accurately record the fact but only share it with your family members with care.
I looked in the online newspaper indexes at the Rochester Public Library and found only 5 references in the 1818 – 1850 index but 97 references in the 1851 – 1897 index. There were many more cases that didn’t make the newspapers. You can do a search of old County Court records to see if the case is recorded. But very few cases of bigamy ever ended up in Court. Most of the time the man or woman that was committing bigamy would end up leaving when found out. That would mean that there would be two broken families.
I found a case of bigamy in a remote part of my family recorded in an unusual place. It was in a Civil Ware pension file. After my relation died in the Civil War, his widow married again after a couple of years. She and her new husband has a daughter, but two years after the marriage she found out that he was married before without getting a divorce. When found out, the new husband took off for parts unknown. She didn’t file for a divorce for another 15 years. and mostly to obtain her pension for her husband’s Civil War service. All the facts were well documented in the Civil War pension file.