Without going off on a tangent. The townie is a nice sturdy bike and would probably serve you very well for a long time but as most who reply to this thread will tell you that it's very important to go to your local bike shop and try out some different bikes and see what really feels good to you.
I also love to ride and bought a Giant Anyroad 1 last year which has served me very well so far. My wife bought the Liv version of the road bike and loves it. Just make sure you take your time and try out several different bikes to find the one that fits your best.
In regards to your weight loss awesome job getting off to a fantastic start. I too have struggled with weight loss most of my life having been in the 400 range before and now down in the lower portion of the 300s working towards a goal of 250. I found that diet mod was good but things really didn't take off for me until I bought a food scale and truly honestly started tracking everything I put in my mouth.
We can exercise all day long but if we put the calories right back in and more then we will not see the results we want. I have been doing weight watchers online with my wife for almost a year and it has worked really well for us. I do not believe it's necessary to pay for a tool to lose weight but I do really like their app. My Fitness Pal (MFP) also has a very good app and community something to check out if you already have not.
Best of luck to you in your journey for a new bike and new life!!!