[M4F] The Twin sister drama

You and your twin sister were inseparable growing up, but adulthood sent you down very different paths. Allison buried herself in nursing, taking endless shifts at the hospital and measuring her worth by how much everyone depended on her, while you bounced from one troubled relationship to another, always believing the next person might finally give you the life you wanted. Despite your differences, you remained fiercely loyal to each other—making what happened next something neither of you could have imagined.

After your latest relationship collapsed, you arrived at our house with two suitcases, swollen eyes, and nowhere else to go. Allison and I welcomed you into our spare bedroom until you could find work and an apartment, but weeks gradually became months. Allison's demanding schedule kept her at the hospital for long stretches, while I ran my own business and was home far more often, leaving the two of us spending increasing amounts of time alone together.

It began innocently: morning coffee, inside jokes, late-night conversations, and confessions neither of us seemed capable of sharing with anyone else. One evening over dinner and wine, I admitted that my marriage had become strained over Allison's decision that she never wanted children, and you confessed that having a family was one of the things you wanted most. The realization that we shared a dream Allison wanted no part of changed something between you, and eventually emotional intimacy crossed a line neither of us could pretend hadn't been crossed.

Looking to play this out with a bunch of drama and initial secrecy during the opening stages of our affair and your pregnancy. I’m open to changing this to a younger sister instead of a twin, and I don’t have to be married.