I was married in Alabama, I lived with my spouse in MS, and now I live in FL and he lives in LA, where do I file for divorce?

How long have you been in Florida? If you have resided in Florida (with an intent to remain here) for at least 6 months and have either a corroborating witness who can testify to that or, preferably, a drivers license issued at least 6 months ago, then Florida is the proper State for you to file a divorce. Where you were married has no bearing on the matter. However, if you have not been in Florida for at least 6 months, then it is possible that MS would have jurisdiction. My suggestion though, if he is no longer in MS either, wait till you have been here for at least 6 months and then file in Florida.