First of all, congrats! That’s amazing that you decided to make such a big change for the better with both your physical health and your outwards appearance.
While wanting to be proud of how you look (your body and what you put on it) can be construed by some as vain, I think it shows respect for yourself.
How you present yourself telegraphs to the world what you think of yourself, and how others should treat you.
By maintaining a healthy weight and putting effort into your appearance, you’re telling the world, “I care about myself; you should care about me too.” That’s awesome.
As for the wool, I wonder if you’re perhaps buying…itchy wool? Go to a suit store and try a few wools of higher quality than what you’ve been wearing. Wool suits and pants made of a finer fiber – think Super 130s and higher – might feel totally fine on your skin.
Of course, the price tag will rise accordingly, but paying more for clothes you actually feel comfortable in seems to be worth the extra cost. It would also be great not to cut off a pretty fundamental suit fabric from consideration in your wardrobe.
If, however, wool continues to make you feel like ants are crawling all over your body (which is obviously no fun), then consider suiting alternatives like cotton, linen, and seersucker in the summer, and corduroy in the winter.
Who knows? Your sensitive skin could be a blessing in that it forces you to be more creative and personal in your style. You’re already on a journey towards evolving your personal style; maybe the fashion gods really want you to go for it.