I've had basil plants last more than a year - you might try adding some compost & bit of fertilizer & see if it puts out new growth. This time of year, some afternoon shade is mandatory for many plants. Older leaves can be tougher & less flavourful, IME.

& you can use the flowers & tender budding tops in cooking as well as the leaves, I chop them up along w/ the rest or sprinkle them over salads.

Here is a link that might be useful: Basil @ Floridata.com

Gator, I'd chop it down to about 1/4 of it's current size. Basil has been very vigorous for me and I do this frequently. New growth should be perfect!

Jo