It sounds like the development of that super-close relationship, and subsequent "loss" of the midwife is aggravated by the fact that you feel a serious void in your life, one that the midwife happens to fill.
But the midwife, however friendly and wonderful, is a paid professional with a specific job to do. That job is easier for her when she gains your confidence, so she should absolutely do that, but she won't be in your life forever.
You need some other way to fill that gap - someone who doesn't have a specific prescribed role, someone whose involvement isn't limited at the outset. That's a hard thing to do: you have to work to develop trust and connection with someone who has no particular incentive to put up with you. But it sounds like you badly need to develop a broader support network, and do that work.