Tomato plants are dying
It looks like your tomatoes have been subject to some foliar diseases and some soft rots. Two common foliar diseases are early blight and septoria but it does not matter which disease it is because the management is the same.
Select disease resistant varieties, remove the lower leaves to slow the upward spread of the disease, keep plants well mulched to minimize soil splashing, water at the base of the plants, provide adequate spacing, and spray with an organic fungicide (fixed copper) early in the season to lessen the spread of the disease. Fungicide treatments can help to protect new or un-infected foliage, they are not curatives.
Harvest the fruit at the blush stage and let it ripen on your counter to prevent, cracks, rots, and insect issues. Remove infected plant material at the end of the season. See our website for more information on early blight and septoria