Glamourgirl,
My spouse hid the secret that she was TS out of deep shame and lifelong repression beginning in very early childhood. She hid it so well that she was suffering an emotional death from it. She didn't tell me until almost 5 years into the marriage. I certainly don't consider her a liar; she was just trying to survive.
So many people suffer for so many years so their partner can be spared pain or inconvenience. It's not a load lightly shared, and usually shared with disastrous results. If you put someone between a rock and a hard place what do you expect? Have you ever used a pressure cooker?
Knowing what it's like from talking to so many people and seeing the changes in my own spouse, I do consider an effort to spare a spouse for years selfless, not selfish. Have you ever ignored a toothache hoping and praying it would go away? It usually only gets worse over time until you have to do something about it.
Life is short, love is rare, and compassion is precious. I hope you can really talk to your partner and understand his journey to this point better. Be kind and repay 7 years of silent suffering by really working out something that you both can truly live with. Perhaps you should check out the books by Helen Boyd?
Good luck to your family. I hope you can work through this.