2001 Subaru Legacy won't start. Needed a jump a few days ago and an alternator, now is dead?

So on Friday I drove my car to class. In the evening, it wouldn't start. I got a jump start, and ran some errands, and the car was able to start without a jump for the remainder of the evening. Later that night I decided to check the battery. It was dead again. So I decided to get another jump the next morning. This time, when the starter pack was connected, the car started, but was behaving erratically, with the windshield wipers waving madly. The car turned off after about 10 seconds. When the pack was connected again, the car would only run while the leads were connected, and would shut off otherwise. Because of this, I took the alternator to my local auto supply store, where they confirmed that the alternator was gone. I bought a new alternator, and installed it today. Before installing it, I noticed that nothing electrical seemed to work except for the clock. Ten seconds after opening the door, that too faded. Upon installing the new alternator, the only thing the starter pack managed to produce was the beeping sound when you leave the key in the ignition. The car would not start. There was no clicking sound from the starter or anything. We tried connecting the starter leads directly to the battery leads (removing the battery from the leads and connecting to the starter). We also installed a new battery and still nothing. We checked some fuses, and couldn't find anything blown. I have no idea what is wrong, though it seems to be electrical. Help