You are correct about the automatics being more efficient. GM (Chevy) has only been buiding reliable Chevy Cruzes for the past year or two. I would totally stay away from the older Cruze as those have a lot of problems. Seriously. The 2012-2015 Civics were known for having lost the "Honda magic" because they drove like they took a step in the wrong direction compared to the 2006-2011. However, they have always been very reliable, even with the CVT. You are considering the 2015 Civic, but you should look for 2014s because they will be a little cheaper and the 2014 is exactly the same car. Skip the Cruze 1LT. Your boyfriend was wrong about the turbo and traction in the snow. Every FWD car will perform similarly. You need snow tires if you want to improve traction. Also, American cars are only marginally (not worth mentioning) cheaper to fix than Japanese cars, but they break down more than Toyotas, Honda, and Mazdas.
I am going to suggest the cars that most people default to for good reasons.
Mazda is a brand that builds reliable cars that don't have the premium purchase price of a Honda. The Mazda3 is a compact car like the Civic and Cruze, but is more fun to drive and reliable. I strongly suggest the Hatchback even if the Sedan gets 1-2 MPG better. The only drawback I see with this car is the road noise and the ride is bumpy (the tradeoffs for being fun to drive). My son has a 2015 and he loves it, though he wants the hatchback, not the sedan. I recommend a 2012 Mazda3 i Touring hatchback. The Touring is the best trim and the 2012s and newer have the much more efficient and more powerful engine. The reason I recommend the hatch is because you get twice the cargo space, visibility is better, and they are more stylish.
The Toyota Corolla may not be the most fun car, but it is the most reliable. Almost all of them last past 200k miles with maintenance and are some of the most reliable cars on the road. This is the practical choice, not the emotional one. The main problem with this car is that the Mazda3 is not just reliable, but is also fun. The Corolla isn't. The Corolla is more comfortable and quieter than the Mazda. The Corolla is the most reliable compact car, but is only slightly better than the Honda or Mazda. I recommend 2011 or newer in the LE or S trim.
Comparing these two to the Civic, I would choose the Mazda first, Civic second, and Corolla third. The 2012 Civic was so bad (in terms of quality and satisfaction, reliability was good) that they updated the Civic the next year, which is almost unheard of. The oldest your should go is 2013, but the 2014 is better. The 2013 and 2014 were actually pretty good cars. I recommend the EX trim, but the LX is also a decent value.
The last I would consider is the Kia Forte. I like this one because they are a great value when bought used because they depreciate quickly. They are reliable and comfortable. I don't recommend a 2014 Forte LX because it doesn't have a backup camera, but the 2014 EX does. The 2015 LX can be had with a package that has a backup camera.
Also if you are going to have kids soon you may want to consider a crossover like a Toyota RAV4 or small wagon like a Kia Soul so you don't have to buy another car abruptly. If you respond with your zip code we could find good car listings to help you. Good luck with your search and please tell us what you buy.