Sorry, honey, but I'm going to side with your husband on this. Preschool is not much more than glorified daycare, in my mind. If he's willing to be present for her at home, maybe provide some opportunities for limited interactions with other kids/parents, no school will work harder than he to provide opportunities for growth and development for your daughter. Summer's coming: how about playdates in the park, swim lessons, dance classes, Music Together classes, etc. Possibilities abound. School can wait. Preferably a long, long time. 2 and 3 year olds are never going to provide the lessons in socialization that you want for your daughter. Think about it: social skills taught by preschoolers? Huh? That will come from you, primarily. She wants you guys for now: enjoy the moment. It WILL pass, and, when she goes forth into the world, it will be with confidence and not fear, because you listened to her, read her cues, obeyed your own instincts, and gave her a most excellent start in life. If you still insist on taking her to school, at least allow dad to stay with her there, preferably the whole time, but maybe transition to part time if you feel she's ready for it. You'll know that she really wants to be there when she is running in, eager for the day to start, and reluctant for it to end. Simply not crying so much is not good enough. She'll only be learning that resistance is futile, conformity is best, and it doesn't matter how you feel, so try not to feel at all. Please don't do that to your daughter. She sounds amazing, and you both sound like wonderful parents who are trying to figure out what's best for her. School isn't it: you are!
I am a mother of 2 homeschooled daughters, ages almost 11 and 15, and have worked in early childhood education throughout my life in various settings.