Transgender is a huge spectrum of behavior and identity. But at its core is a mismatch from the physical sex and the mental or self identity of sex. There are strong stereotypes of what a man or woman should behave and appear. Therefore, these factors interplay to generate many subcategories in transgenderism.
Overall, there is a huge amount of prejudice, anger, and fear focused on people who do not match these "norms". Gay and lesbian have managed to improve these issues but it is my opinion that these people generally aren't in transgender groups. They usually identify as their biology but desire the same biology sexually. (A transwoman is very likely to want men but don't identify as gay due to the man wants man -- it is woman (in male body) wants man.)
So, a man with breasts (especially large) acting like a man violates the manly stereotype and thus the social awkwardness is extreme. I see them getting surgery or dressing to disguise. It would be a very unusual and strong man have a lifestyle of a large breasted man presentation. So, this why I think you don't see examples as they are closeted. Also, most feel breasts is a woman only feature (forgetting it is a secondary sexual development) and thus a person with them must be female. I got to witness this social expection with a man doing something similar as me. Society expects a binary gender and it just isn't true.
As for myself, I started with this way of life in mind, a large breasted man. However as I exposed myself to estrogen like substances and their effects took hold, I realized my self identity had more feminine characteristics than expected. As my body has feminized, I found women's clothing much more comfortable and thus I'm dressing more often in them. I have found it is fun having more choices. But in the end, I still don't feel I am "woman" but nor do I feel I am "man" either. Fun place to be..
This is where I'm at and learning about myself.
@Smala, if you haven't considered this aspect of your decision of growing breasts then I think you should. It will impact your marriage and it would be best to give a consistent message over time rather than "changing all the time" and confusing her to the point she feels you're been lying. If your feelings on the matter is cloudy (like mine) then trying to explain your understanding thus far is better than nothing.
DJ