To help repel squash beetle.. plant your summer squash and zucchini in among your radishes.
Don't pull all your radishes, let some go to seed. Radishes have a pretty little flower and will
also help repel cucumber beetle. If you have a bad infestation of squash beetle (and you are loath to use poisons) remove all the infected squash, foliage etc. - burn (do not compost) and then plant petunias, radishes or nasturtiums where the squash/zucchini was. Don't plant squash in the same place next season. (this includes pumpkins) These methods will help (maybe not prevent all) rid your garden of these nasty pests.
Telling another avid gardener your squash beetle/loss of zucchini story will probably net you a few of their bountiful harvest. There's always enough zucchini to go around.