I typed the following a couple of hours ago in reply to you, KaitlynFairchild . ThePurported has made the same point, and much more eloquently and pithily than I, but I will post it anyway.
Look, the spousal veto should not be removed unless there is first a major reform of the current divorce legislation, which is utterly archaic, but won't be changing any time soon thanks to Brexit.
The spouse needs to have some control over what is happening to their life. This is not all about the "true identity" of the transitioner. This is also about the identity and dignity of the spouse. It's funny how you are fully prepared to back a wholesale change in the law based on someone's nebulous feelings, and yet the feelings of the people they devastate are viewed as irrelevant.
With the veto in tact, the spouse can have some control over the process and how it will effect her. If she knows her spouse wants to transition, she can get her ducks in a row before a GRC is granted, including starting and completing the divorce process if necessary.
As the divorce laws currently stand, if the veto is removed and self ID comes into place to allow a GRC to be granted with no proof or process, then there is nothing to stop the wife coming home one day and, out of the blue, with absolutely no warning whatsoever, finding she is in a same sex marriage.
She is then stuck with having not only to deal with the shock of this, but with the burden to then have exit the marriage, whilst already being mandated by law as being a lesbian, because this will be the only way the marriage can exist post GRC. She will have the usual divorce routes, the 2 year separation with consent (5 years if no consent), adultery or desertion(which may or may not have happened) or the unreasonable behaviour route.
With regard to the latter, it would not surprise me at all if the next bit of lobbying from the trans rights lobby is to try to remove expressions of "true self" from the definition of unreasonable behaviour, on the grounds that it is transphobic to suggest that transitioning activities (hormones, surgery, dress, pronoun changes, sexual identity changes) are unreasonable ones. I can see women being accused of being transphobes and homophobes for even suggesting that they find their husband's feminine pastimes intolerable.