Hi, Brianna.
You have to do what's best for you, whether that is transitioning or not transitioning. Only you can decide that.
I am a little bit farther along the path than you, but not by much. (I am hoping to start HRT in a month or two.) If I had never figured out that I was transgender, I would probably have continued my life as a miserable man until I died. Figuring it out meant (for me) that there was no going back. I could never un-know the fact that I was transgender and could never forget the possibility of transition. The regret of knowing that I would never get to be myself would have killed me. YMMV
When it came to coming out to my wife, like you, I would not have been able to see a therapist in secret. The secrecy alone would have ended our marriage. So I knew I had to come out to her "cold turkey". It was a gamble, and I knew that the odds were more than 50% that it would end badly for the marriage. But I still had to do it in order to have a chance to be me.
Sometimes you get lucky. My wife accepted me for who I am. She believes that the greatest tragedy is for people to not be themselves. I think she is right.
We are taught to ignore ourselves and our own needs. We tend to evaluate the risks as "Say nothing and the marriage survives" versus "Speak up and the marriage ends." A more accurate and healthier assessment, including your own worth in the equation, might be, "Say nothing, the marriage survives, and I never get to be myself (and maybe the marriage fails anyway)" versus "Speak up, and maybe the marriage survives and maybe it doesn't, but either way, I get to be myself."
I know it is a tough choice. It took me literally months to make it. I made it with the help of the kind people here. Whatever you choose, we are here for you.