The debt-to-income ratio is a direct reflection of your ability to afford the payment. Depending on your credit score and the amount of equity you are looking to take out of the home, yes there are lenders who will exceed 45%. 50% is not unheard of, and if you have stellar credit and very stable income in some select cases you can go to 55%. That is about it though. It's normally determined by Fannie Mae/Freddie Mac/FHA's underwriting program. A physical person (the underwriter) doesn't have the authority to exceed debt-to-income guidelines.
If your debt to income ratio is still too high, then you will want to check with a broker who deals with portfolio lenders in order to get a specialized program. The rate will be higher and you may need to do an ARM as opposed to a fixed rate, but that may be the only way.
If you happen to be 62 or older, then you could also look into a reverse mortgage. No payments, no credit or income requirements.
Best of luck!