Wingbar - You may have to do what i had to do. I instructed for several years and it slowly drained my finances until i was getting into trouble. I had to give up full time instructing and return to my previous career which i left nine years ago - luckily i managed to double my income overnight and carry on instructing part time which kept me current. Obviously going back into an office after several years of flying was very painful but i had no choice.
I have just been offered a TP job and i will be taking another pay cut but at least the salary is respectable and regular. The important thing is not to give up and try to get some good contacts in the industry which i think is by far the best way of getting in.
Good luck