A way to show no relationship exists

Hi all,
I am hoping someone may have an answer to something that has me stumped.
I have a list of client relationships, its easy to show where a relationship between 2 clients exists, I can just pivot the data.
As a salesman I need to identify where an opportunity exists IE where no relationship between 2 clients exists.

I have a list of 200 clients, i need a fast easy way to show where no relationship exists when I select a client?

Client 1 Client 7
Client 1 Client 8
Client 1 Client 9
Client 1 Client 10
Client 1 Client 11
Client 1 Client 12
Client 2 Client 7
Client 2 Client 8
Client 2 Client 9
Client 2 Client 10

So if i was to select Client 11 it would show that they have no relationship with Client 2 or 1.

Essentially I think of if it was in a pivot table:If i were to apply a filter on the column and selected Client 1, it would only show me Client 27,28, 30 & 32. I need something to show me all the missing 0's.
Count of Agreement Amp ID Column Labels
Row Labels Client 1
Client 1 0
Client 2 0
Client 3 0
Client 4 0
Client 5 0
Client 6 0
Client 7 0
Client 8 0
Client 9 0
Client 10 0
Client 11 0
Client 12 0
Client 13 0
Client 14 0
Client 15 0
Client 16 0
Client 17 0
Client 18 0
Client 19 0
Client 20 0
Client 21 0
Client 22 0
Client 23 0
Client 24 0
Client 25 0
Client 26 0
Client 27 35
Client 28 1
Client 29 0
Client 30 1
Client 31 0
Client 32 1

I hope this makes sense.
Any help would be appreciated.

Thanks
Chris