The mother and I split up and she moved to her moms house. Then I find out she moved to Michigan with an ex boyfriend a couple days later. She didn't tell me or even let me see him before she left. She even parked the truck I let her use in a parking lot with keys stashed in the wheel well

If there is no order for custody and visitation then yes she can move. That doesn't mean you can't bring the child back. You need to file locally, IMMEDIATELY for custody and visitation. If she is allowed to stay in MI long enough to establish residency, then she can file there. But if you file immediately, jurisdiction will be where the child was born.

I suggest contacting an attorney to file.

My son was born in Wisconsin and she moved back to Florida where I lived. She was here for 8 months and then moved to Michigan

My son was born in Wisconsin and she moved back to Florida where I lived. She was here for 8 months and then moved to Michigan

Then you have six months, from the time they moved, to file in Florida.