Have you tried just spraying-off the aphids with the hose? Also, try sprinkling DT (diatomaceous earth) around the base of the plants.... ants may be carrying the aphids to the plants as "cows"; by putting down DT you will stop this. This works for Scale too.

I don't see signs of aphids either. Aphids don't tear/eat leaves like in the last pic. Look for small caterpillars.

Is this being grown in a pot indoors?

Houzz won't let me edit .... There's probably a caterpillar in that dark mess/web in the last pic.

This was cross-posted in the FL gardening forum, so I am presuming you live here, somewhere?

FWIW, this is just the beginning of vegetable gardening season in much of the state. It's been way too hot, humid and buggy to grow much of anything. Some fruiting veggies like tomatoes cannot set fruit when temperatures are too high. They will still bloom, but no fruits will develop. Also, cucumbers are not always self pollinating, and even when they are, they have separate male & female flowers, so if there are female flowers(tiny fruits at the base) but no males(no tiny fruit at the base) pollination cannot occur.

Looks to me like caterpillar damage is destroying your plants, as well. If you examine the undersides of the leaves, you might find tiny bright green caterpillars that blend in, along the ribs of the leaves.

IMPE, it's often not worth the trouble, effort and expense to try to fight the bugs at this point, since the plants may already be so weakened they will never do much better.

You might consider starting over.

Here's a link to the University of FL's veggie gardening handbook, with recommended planting dates for our different zones:

edis.ifas.ufl.edu/vh021

Completely agree with the others--if you're in FL, time to start over.