This is an excellent thread ... one of the best set of responses to a "Choose a bike for me" posts.
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aabb, there are a lot of people here who really know their stuff really trying to help you enjoy cycling. We all have different modes of expression ... and a lot of us are frustrated by trying repeatedly to help an endless stream of posters who come here asking the same questions and not listening to the answers .... not your fault, just some context so you will understand people's responses.
I can tell you exactly what I think you should do: by a Giant Contend of Fuji Sportif .... or for more gravelly work, a Yari .... in your size and with Sora running gear at least, and ride for a season. Spend about $1,000 or $1,200 but not a lot more. You can get so much bike for that money it is ridiculous .... and when you have several thousand miles on the bike, you will have laundry list of likes and dislikes, and your next purchase will be much more focused.
That said .... buy that Cervelo if you like it. At that price, if it isn't for you, you can turn it over for $2000 after a season, and if you like it, it will have been a good deal. That is another option. And I cannot say what will work for you .... because You don't know what will work for you. You might want a Camaro, or a Corvette, or a Ferrari, or a 4x4 Jeep. No one knows ... Heck, you might want a mini-van.
Seriously .... Go Ride Bikes.
Never go to a bike shop with money. Leave the credit cards at home, so you won't fall in love with an evil-hearted temptress. Be honest with the staff, and ride Several bikes at each shop. No, you will not learn a lot as far as how a bike will suit you six months from now, when your body will have changed significantly from continued riding .... but you will at least have a large sample of impressions, so that you can make comparisons. You will be able to say what was better or worse between what you have tried .... and maybe rule out some stuff.
Seriously ... your body today is nothing like the body you will have at the end of the season if you ride for six or eight months. "Fit" will change every few weeks as your various muscle groups adapt and grow. Also, your differing cycling passions will surface ... you might find that all you really want to do is trail riding, for all anyone knows.
Just Get On a Bike .... over and over again. Try Everything. And go into it knowing that stuff you hate today might be what you love tomorrow. Fast handling, a stiff frame, a short wheelbase, a long, low riding position ... you might hate them today and love them in six months ... or vice versa. .... Know that. Know that you are buying a First bike, not The Bike. it might turn out to be the same bike you will be riding in ten years, or you may replace it in ten weeks. Maybe you will stress less thinking this way.
But yeah ... RIDE BIKES. AThere is absolutely no relationship between sitting in front of a PC and riding bikes ... I'd win every Tour de France otherwise. Get out and Experience what is out there. It can't hurt and it will probably help. And in a few months You will be the person here with a bunch of knowledge helping new riders get started.