It has been raining heavily here for this entire month and I have lost one tomato plant to sudden wilting (no yellowing) over night and then the plant dies but the leaves will remain green till death. At first I eliminated the wilted plant and didn’t get any other wilting but today after 3 weeks another plant had died overnight. Most worrying is that this plant is sharing a hole with another tomato but its neighbor is very fine. Any assistance is highly appreciated.
The plants likely developed a fungal issue from all the rain. If so, there's little you can do but for those still thriving I would recommend moving them, if feasible, to prevent spreading of the spores. Improving drainage to the area and application of a fungicide may also help. Here is more information on wilting in tomatoes: https://www.gardeningknowhow.com/edible/vegetables/tomato/wilting-tomato-plants.htm