The fact that one party to a marriage is a British citizen does not automatically entitle that person to petition for divorce in the English courts.
As a general summary of a complicated situation, a petition in the English courts is possible if one or both of the parties is habitually resident in England. Alternatively, it is possible if one or both of the parties is ' domiciled ' in England and Wales. ' Domicile ' is a very important concept in international law but as a general rule it means the country which you call ' home ' and can change from time to time.
I have to stress this is a very broad brush statement, but in practical terms, if you do not know where your husband is, you won't be able to prove domicile or habitual residence, and therefore I would say you would have to petition in the state where you happen to reside.
Except - England is very maybe his residence for now. And in my state they will requare to get the evidence - he has been contacted or so.
Anyway, should find that piece of shit first.