Were just after going through this process. We got married in January and as soon as we were married everything changed on the mortgage.
Basically my wifes salary is not taken into account, but my salary now has to support the mortgage and for both of us to live on. i.e. they say she earns €0.
BOI do take some things into account, such as if she was not working then I would get her tax credit, thus upping my salary. However AIB will not do this, they simply say she earns nothing...
It's very frustrating seeing as her salary is quite impressive just to be discarded. Thankfully like I said BOI can work with your options.