Two Tours Back to Back - Paris & London

The Eurostar train will cost less than $100 if you book far enough ahead, and be faster than any flight when you consider airport time. It's a lot simpler than flying. You do have to arrive at the station about an hour before boarding, but it takes you from central Paris to central London in just over two hours. I don't know why you wouldn't be comfortable taking the train alone, many people do. But I don't have the medical credentials to opine on your sanity. ;-)

It should be easy to book hotel nights in both cities, especially with enough lead time. Ideally you'd stay at the same hotels as on the tours, but you'll have to look at availability and cost. If that's not doable, look for others nearby so you don't spend too much time transferring between them.

and not comfortable taking the train by myself.

Why? There is nothing strange about taking a train, it is a lot easier than flying.

Am I crazy for not taking the train?

Yes

If you are comfortable taking a flight by yourself, you should be just fine on the train by yourself. The train is much easier if you take into account getting to and from the airports on either end. Maybe if you tell us what concerns you, we can allay your fears.

Another vote for rail travel. When you signed up for the tours, you should have received the info about which hotel you were staying at. After many tours with a Rick, I’ve realized you should contact them directly by email or using their website ASAP to secure additional nights. Check the info you received because they might give you a discounted rate. Let them know you’re on a Rick Steves tour.

Another vote for rail travel. To get best ticket price, buy your tickets as early as possible. The benefit of taking the train is that you are going from the center of one city to the center of another. No trek to and from the airport with extra transportation costs and dragging your luggage around.
When you signed up for the tours, you should have received the info about which hotel you were staying at. After many tours with a Rick, I’ve realized you should contact them directly by email or using their website ASAP to secure additional nights. Check the info you received because they might give you a discounted rate. Let them know you’re on a Rick Steves tour.

Train. We did the 7 day London then popped over by Eurostar train to catch the 11day Paris and heart of France. Very easy.... just planned our route using the tube and metro to get to our hotels with ease. If you go by train , cheaper to book early

You Tube is your friend when thinking about taking a new form of transport.

Search for “How to travel on Eurostar” videos and watch some. It will build your confidence if you see how others do the same trip. It will also help develop a sense of familiarity with what the stations and trains look like.

You will be riding on the London Underground during your London tour and on the Paris metro during your Paris tours. Your guides will give you a lesson on this, but I’d watch a few you tube videos on those as well.

You are “ not” crazy if you don’t take the train. Do what you feel comfortable doing. It is easy to do though. I’m pretty sure your tour guide will help you with getting to the train station if you decide to train it. But, buy the ticket soon to save money.

Is it because you’ve never traveled by train before, but you’re used to flying? If so, let me sing the praises of European train travel! We really don’t have anything to compare it to in the US, and it’s so easy and convenient! The workers in the Paris train stations speak English if you need help finding your track. Also, I think the main Paris airport is terribly inefficient and confusing, not to mention way outside city center - much easier, IMHO, to get to Gare du Nord train station which is connected to Metro and city center.

If you don’t want to take the train by yourself, that’s fine.
In addition to YouTube videos, take a look at the excellent train website, The Man in Seattle 61.
He has an entire section on traveling by Eurostar between London and Paris. There are also pictures showing you what to expect at the stations and on board. He covers everything including how to buy your ticket.
There are always employees on the track to show you where to board and your fellow passengers will be helpful. There are bathrooms at the end of each car. You will have a reserved seat and there are announcements and lots of signs .
Check it out and then you can decide.
www.seat61.com

The Man in Seat 61 also has a pretty good video guide on how it works: https://www.youtube.com/watch?v=l5RAYy9Uymc