During your landing interview, the Immigration Officer will see your spouse visa and open a line of questioning like...
How long have you been out of the country? (4 months)
Are you still married? (yes)
Is your husband in the UK? (no)
Where is he? (middle east)
Is he living there? (yes)
Are you living with him there (yes)
How long has he been been living there (...)
At that point the IO will ask you to wait and he will go away to check your details on the secured computer. He will then return, possibly with the Chief, and ask a few more questions. Nobody can predict exactly what he will ask, but it's likely to be about what you are doing on this trip to the UK and if you intend to renew your visa in October. The answers you give will determine whether your spouse visa is still valid or not.
If they decide your spouse visa is still valid, you'll get stamped in and can proceed to start your visit.
If they decide that a spouse visa is not right for your situation, they will ask you to sit down at one of the waiting chairs until they finish sorting out the other people. As long as you have played it straight up, you'll be fine. There is no hard requirement to inform them when you move away and based upon what you wrote you haven't broken any rules. They have several options: curtail your spouse visa to expire in a few weeks time; or curtail your spouse visa to expire immediately and give you a temporary admission as a visitor; or admit you as a visitor on your own passport (if you qualify for visa upon arrival). Finally, if they decide to curtail immediately and your passport is issued by a visa-national country, matters will be worse; but this would be an unduly harsh measure and (to my mind) unfair.
For your other question about applying for a visitor visa... Yes, you can do that. But a person can hold only one immigration status at a time, so if they issue a visitor visa, your spouse status will be forfeited without knowing whether or not it was still valid. Also, a consular officer at a British issuing post is not authorized to cancel a person's existing visa (it's unlawful), they will have to make a referral to the Home Office and that will take a lot longer.
NOTE: everybody can have their opinion but the real decision lies with the IO, who is required to get clearance from the Chief in situations like these.
NOTE: what I have described is a likely scenario. For all I know they could wave you through with no questions at all.