I think I'm a big girl on a road bike (5'5" and 220). I have several bikes and always prefer the roadie. I am certain I look ridiculous in my lycra shorts or knickers, but I'm comfy and exercising. So, do what makes you feel good!!! It tooks several short rides to get accustomed the road bike, so just keep at it! Here's a pic of me torturing one of my bikes at a Trek Breast Cancer Awareness Ride:
2018 Trek Silque SLR6 - Selle SMP Glider
2018 Specialized Dolce EVO Comp - Selle SMP Glider
2011 Trek Madone 5.2 WSD -Selle SMP Glider
2013 Giant TCX W - Oura 143
I love to see large women doing something seriously athletic. Why walk when you can feel the wind in your face and the joy of moving fast? I am a larger women (although I have lost about 25 pounds since I got back into riding in September) and I take great pride in the fact that my ample bottom and thick, strong legs make me a powerful cyclist. You go girl!!!
Welcome Zen. Like anything it takes a little time. It probably took me a good four weeks getting comfortable and this forum helped me out a lot. I also came from strictly riding Mtb's. As you learn handling techniques you will get comfortable. I practiced alot in big parking lots. Before you know it - it will feel natural.
I took the new bike out for a 65km ride yesterday. It was a cycle event / race and it took me ages to finish (which is another post i will make shortly) but it gave me a good spin out on the new bike. I was REALLY nervous about it, but once i got going i was fine.