Train Seating

Take a look at The Man in Seat 61.

According to the Man in Seat 61, only on some routes. Your other option is to book facing seats across a table so that on seat will always be facing forward. In first class, you can do that on the single side and have the whole table to yourself or in second class you may have to share.

I have the same problem with motion sickness. As far as I can tell, it isn't possible to know which direction your reserved seats will face. I have sat in the same class seats that did face in the forward direction that were not my reserved seats. Conductors that I've reached out to when I did this have told me that as long as those seats weren't taken and were the same class/price tickets that that was fine.
I also take Bonine (non-drowsy motion sickness meds that last for 24 hours) when I can remember.

I always wonder why people from outside Europe are more prone to motion sickness on trains than Europeans.

There usually is no way to guarantee forward facing seats. The railways do not put a lot of thought in to that as the vast majority of people actually do not care. Furthermore on Nice to Paris the train will reverse direction in Marseilles, so whichever seat you get it will be facing backwards half of the time.

What you can do is:
- Book first class.
- Select two facing seats. Than you and your husband can swap seats when the train changes direction.

When choosing train seats in second class, we always book at a 4 person table across from each other. We have been on several trains when the train reverses directions leaving the next station. We and our table mates all get up and let the more motion prone person sit in the forward facing direction. This has happened with couples from various countries, not just Americans.

Even if you take the time to try to figure out exactly what seat is facing the way you want they can change it on you. This happened to me a couple years ago on 2 of the 5 train reservations I'd made.

I agree with WengenK, choose seats facing each other then you and your husband can swap when the direction changes.
As for a trick to ensure you have forward facing seats...the seating charts on SNCF connect do show which direction the train car will be going when you are choosing your seats. However, it is subject to change.

Bon courage! And I hope your journey back to Paris is less...queasy. ;-)

It is not possible to know in advance which way you will be facing. In fact, orientation can change in route, which is why half the seats face one direction and the other half face the opposite direction.

When choosing train seats in second class, we always book at a 4 person table across from each other. We have been on several trains when the train reverses directions leaving the next station. We and our table mates all get up and let the more motion prone person sit in the forward facing direction. This has happened with couples from various countries, not just Americans.

What an excellent approach!

I always try to face forward, too.
It appears the new SNCF TGV "Oceane" duplex trains have First class seats that can be turned around at the push of a button.
Learned this from always-helpful The Man in Seat 61!

The reason that trains have half the seats facing one way, and half the other is because, yes, the vast majority of people do not care. And yes, I do observe that being uncomfortable with riding backwards in a train is more common with people that come from countries where train travel is not that common. In countries where people travel a lot by train nobody really cares.

And anyway, trains change direction all the time, so even if you started in a forward facing seat, there is no guarantee you will be facing that way the whole trip. I was recently on a train in Spain that started out with almost everyone sitting facing forward, but after reversing at an intermediate station literally almost everyone was facing backwards...

Personally I do believe it is mostly just imaginary, and lack of experience.

To this day, I still can't ride ten minutes in the backseat of a car without getting sick.

It does not appear that train travel, outside of maybe the RERs, will be a solution for you. There is no way to assure seat orientation when purchasing tickets. All Paris trains, for example, enter the station one direction and depart the other. Trains could enter an intermediate station en route and change orientation.

Consider flying from NCE to ORY or CDG, it will be faster and can cost a lot less.

@StellaB: I am exactly like you where it comes to car travel. It is even to the point I will always volunteer to drive, as I cannot bear being a passenger in a car.

But I never have issues on a train. In fact, I do not know anyone personally who has issues on a train. And I have never heard from anyone having issues with motion sickness on a train unless they were not from Europe...

So I guess a lot of people assume that if they are susceptible to car sickness they will suffer on a train as well. And if you do not have a lot of experience travelling by train you indeed do not experience that it is nothing like car travel. Nothing at all.