What I've learned from this forum is determinate type tomatoes bear most of fruits in the same tree around same time and after their job is done - producing fruit for us- they literally die while indeterminate variety continue to grow taller and produce fruits until disease or frost kills them.

What variety of tomatoes do you grow?

Preppy, My determinate's are dying but my ID's are still kicking, putting on new growth. I planted a fall crop in early July (zone 7) and they are starting to bloom. I'm Not sure, but in zone 8, maybe you can start a new crop?

Why are they dying?

Sometimes a lack of watering is blamed when the real problem is wilts and blights have withered most of the plant. If the whole plant is the same stage of wilt/dryness that might really be a moisture problem. If yellow or brown leaves move from the bottom of the plant towards the top, that is a good indicator that you need to:
-- spray with compost tea
-- keep branches off ground and from touching other plants
-- water the base of the plant, not the whole thing
-- next year space the plants further apart.

those plants do have things that look like spider web around the leaves.

yes, since those things are growing on those leaves, so i tend to watch the whole plants to wash them.

oh, yes, i did want to grow more, so i planted a lot close by. why does that cause the plants to die early?