If your dough isn't holding together, it's too dry and too short. One solution [snicker] is to add more water, work it more, and hope a longer rest compensates for the toughness both changes add.
If you're not a vegetarian, quit using Crisco and switch to something else. Many supers sell an extra cheap brand that includes animal drippings. This will work better than the new Crisco. It's also a natural segue for the best solution.
Lard. There's a been a big move back to lard in the pro and advanced amateur worlds. Of course, some of us trogs never left. It simply works better. Your crusts will be light, flaky, and "melt in your mouth." Much better than they ever were with Crisco.
Biscuits to die for. Better for frying, too -- much less oily.
Whatever health benefits come from Crisco or other veg shortenings are slight. Lard is also "Zero-Transfat." Lard has a very high good cholestrol/bad cholestrol ratio (HDL/LDL), used in crust it doesn't substantially add to the dietary fat in a dish (you're worried about fat with quiche?), nor increase the calorie count. If you're squeamish, you'll get over it the first time anyone compliments your crust which will come the first time. If they're squeamish, don't tell them.
You don't have to use wonderful, special, extra-fresh, gourmet leaf lard either. Just get regular, plain-jane lard. If you live in an area with any Hispanic markets, they have it. If all the labels are in Spanish, it's called "manteca." Write it down on a piece of paper and take it with you. Asians use it by the ton, too. If you live in the west, look for Farmer John lard -- comes in a 5 lb white plastic bucket with a red top. Good stuff.
Hope this helps,