Crib Training - HOW?!?!

So a little background on the situation at hand. I had severe postpartum anxiety for the first two weeks after giving birth. I was hospitalized twice within those two weeks it was so bad and so naturally I wanted my baby to sleep with me so I knew she was breathing and I could wake her up if she stopped. Well we did bed-sharing as safely as we could. She was in an infant sleeper (photo attached showing the product and how we slept) and slept in that in between us. Now she’s three months old and sleeps only in the sleeper but in her crib. 🤦🏻‍♀️ Please no bashing, I’m trying to correct my mistake. She always has slept through the night since the day she was born. But now after trying to get her to sleep swaddled alone in her crib, she won’t sleep for very long. It’s like she’s taking mini naps. I don’t know what to do! How did you mamas manage to transition?