She wasn't when she made her first baby with him. It also happens that Florida hasn't recognized common-law marriages since 1968, so technically they were not common-law married at any point in time.
Technically she is married to him byway of common law.
Technically she is not, per Florida statute section 741.211.
Maybe she's embarassed for being abandoned after all that time.
Embarrassment didn't stop her from finding at least one other man to make babies with. A person with a half a brain would say, "Gee, if my 'fiancé' would dump me after ten years or so, maybe I shouldn't be opening my knees to another baby-maker without a wedding ring?"
I believe I said "many states". I wasn't sure whether Florida recognized common law marriage.
Why is everyone assuming that that she had another relationship after her children's father left?