Marrying or having children is a giant step to take with a partner, because they are decisions that are accompanied by great consequences and that in the case regret can have very high costs, especially for the children.
In your normal life, you would share only a few hours a day with your partner, and many of the decisions that should be made are decisions without major consequences and that without underestimating, seem much simpler. (obviously having children, buying an apartment or getting married does not enter at this point)
When you travel, however, you are practically all the time with the other person. You have no spaces for you, you have no friends to distract, and you also have to make decisions almost daily. Where to sleep, what or where to eat, be aware of whether or not the budget is sufficient, among many other decisions that must be taken day by day. Even after a fight, you are still one next to the other.
Worst of all, or what makes it more difficult, is that as a baby, lack of food or sleep (something common while traveling) puts us in a much more sensitive state, so discussions are much more common than in “normal life.”
All of the above, make a trip, a very intense love test, which can strengthen your relationship, or make it end. It is a test of knowledge and real acceptance, in which one lives daily with the cyclic changes of humor, and pushes you to keep going forward even though you are in the middle of a fight.
On the other hand, despite all the above, being alone, generates a much more intimate relationship than in normal life, which makes certain things easier. This creates a subsequent challenge when returning to “normal life”, in which the change must be faced. To come back to share with friends and family, can be a big deal when coming back, but if you could go through before, it shouldn’t be a problem.
If all of the above is overcome and assumed wisely, the chances of being successful in the following challenges are much greater, although as always not decisive.