Don't know if you found it yet, but there is a very active community on this site for spouses.

https://www.dailystrength.org/group/spouses-of-transgender

It's a lot to deal with, especially in the beginning. I hope you hold back judgement and just take it a day at a time as the two of you decide how to proceed. There is a wealth of information in the spouses group. I'd start there if you haven't already.

What is he expecting of you? The same thing happened with my former mother in law. However, it caught her completely off guard. She noticed that he was growing breast and asked him about it and he told her that he always wanted to be a woman but that should not affect their marriage. She disagreed saying she married a man not a woman and ended the marriage. It is a lot to try to understand. Don't make any rushed decisions, try to consider both sides of the situation and even if its something you don't want try to be supportive and respectful.

Thank you all for taking the time to respond. I truly appreciate it.
This is most definitely something my spouse and I will work on together , to see what the future holds for us.
Thank you again!

I'm not really sure how you should feel. Its an odd position to be in. I guess the only thing I can really offer is to remember that he hasn't changed. In the long run he has opened up to you far more than he ever had in the past. In a perfect world that kind of opening up should make a relationship stronger, however this isn't a perfect world. Are you okay with the idea of being with a woman? Is he planning to go all the way through transition. At what point will your comfort level be compromised. If you were say Bi, it may not be a thing, but if you are completely straight it could be. Depending on how big a part sex plays in your relationship will also determine a certain amount of it as well. The hormones are often (not always but often) a libido killer. The Testosterone Blockers being the primary culprit. Thing is, it will likely be something that will take him a while to go through. The absolute fastest you can do it is 1 year. Odds are it will take him much longer than that depending on how much he has planned and how bad his issues with it are. I am in it for 9 years now and working toward surgery here hopefully in the next year. So you may have a lot of time with him with next to no changes. So keep the communication between you both open, make sure he listens to your side and talk about it often. See where you both are and where you can compromise. That is about the best thing I can say.