So you had no choice but to stay in a compromised location; when this happens you need to be able to adapt your set-up. You say there was no time for a more elaborate set-up, that's why it failed; you didn't take the time to properly set-up for the conditions.
Many good ideas have been shared here, but you shoot each one down: it was dark, not enough time, no choice in site selection...You need to rethink your decision making paradigm; if all these conditions existed at the time of arrival maybe you should have been in a tent to begin with. However, there are many options to maximize a location and set-up; I'm only going to cover two which haven't been covered yet.
1) Abandon the tarp. Do you really need it? Is it going to rain? With high winds you don't generally get heavy dew. So you may not have needed the tarp anyway.
2) Have as a back up a hammock sock/weather shield. This can be used in lieu of a tarp in windy conditions to counter heavy dew and rain.
One solution that was mentioned is to use multiple stakes per guy point. you said the stake was bent in half so either you didn't have it all the way in the ground properly (for high wind), or the ground was soft enough to cause the stake to dredge and then pull out. Avoid round stakes for this type of set-up as well, the angled stakes get a better bite.
If it was because you didn't have the stake in correctly, learn to place a stake for maximum holding power. A good angle and driven all the way to grade offers the best holding power.
If the ground was soft using an additional stake will increase the holding power.