JK Rowling made a really smart choice – I think – in making Voldemort’s story start with his mother, Merope Gaunt, rather than himself. I think it gave a lot of depth to the character that he would have otherwise been missing, and it serves one other purpose that I’ll discuss later. For now, let’s talk about Merope.
Merope lived in a time when women had few rights to begin with (the early 20th century), and most of those rights were claimed by the rich and beautiful. Merope, on the other hand, was poor, rather plain, and completely under the thumb of her father & brother, who clearly mentally and emotionally abused her (we can assume they physically abused her also, but I don’t think it’s shown in canon). The only way she was ever going to get out from under their control was to marry, and that seemed like a wild pipe dream – after all, she was almost never allowed to leave the house, and she was plain and odd besides. She had very very little chance of ever getting out from under her abusive family.
So, when her father and brother were locked up and stopped (temporarily) from terrorizing her, she seized her chance and used a love potion on the richest (and most attractive) guy in town, so he could get her away from her life. And they were married and conceived a child – and Merope could no longer live with herself for keeping Tom there against his will, so she stopped giving him the love potion – and he was horrified at the life he’d been living, and left her. So now she’s in a worse position than she ever was. She can’t go back to her family (not only did she steal from them and desert them, but she’s pregnant with a half-blood child), she’s pregnant and alone with no marketable skills and no chance of making it in the world. What is she supposed to do?
Whatever her choices were, she ended up dying shortly after giving birth to her son – in canon it is at least suggested that she simply gave up on life; we don’t really know. We only know that this is how Lord Voldemort came into the world, and it obviously paid a huge part in shaping him to be who he was as an adult.