This is a very sad tale. Many people on here have worked for each other, put work each others way and swapped valuable knowledge, but when the unscrupulous do this kind of thing it's unforgivable. 7 months and no contact means taking you as a mug, there can't be any excuses.
You will probably be paid out of the blue now and they will get away with it. Then some other trusting soul will become their next victim.