With no specifics we're all shooting in the dark here, but if it stays 'processing' for days and you have no obvious way to tell what it's doing, it may be worth checking for blocking as well.

Set the blocking process report with sp_configure. A value of 30 should be fine (checking for blocking every 30 secs). Then set a server-side trace to capture the blocking events. If after a few days there is nothing in the trace you will have eliminated blocking as a culprit. If you do get fish in the net, you'll know what holds you back.;-)