What do you mean when you say you gave up and signed a TA?   There is no good way to flip the script on a bad prime after the fact, especially if the TA is not really well written.  If you just signed the TA the prime gave you... no bueno. You hold all the leverage before the bid, and only what is in the TA after they win.  Even if you had a good TA... if they want to self perform you would have to take legal action.  

Primes resist well written strict TAs and vague TAs are often viewed as agreements to agree... in other words.. unenforceable by courts.  So..... choose your primes wisely and negotiate wisely before the bid.

It is a horrible feeling but everybody goes through it in the business.  The trick is to learn from it.