Try it, you'll like it!
I started commuting *home* from work first. I carpooled in with a friend, loaded the bike, then rode it home from work. That worked fine. I did have to negotiate some busier roads, but it was no problem.
Then, on bike to work day, I rode both to and from work. Now I'm hooked on riding in the morning! I discovered that when I leave bright and early to go to work (ok, it's really early...5:30...but I have 17 miles to go), there is NO traffic on those roads. I get to listen to the birds and enjoy the morning.
And with the left turns...do what you need to do!
I still have to do that to feel comfortable sometimes. The more I've ridden, the more comfortable I've gotten with taking the lane to make left turns instead of hopping off the road to walk the crosswalks.
2007 Trek 5000
2009 Jamis Coda
1972 Schwinn Suburban
"I rejoice every time I see a woman ride by on a bike. It gives her a feeling of self-reliance and independence the moment she takes her seat; and away she goes, the picture of untrammelled womanhood."
Susan B. Anthony, 1896