How do I fix this run together sentence?

Even though Jane Falk, the protagonist was upset at first after finding out that her husband had been killed in a carriage accident and went to up to her room to grieve alone, she stared out the window and thought about all the freedom that she could have now that her husband is gone.

It's not really a run on sentence.

However, it would be easier to read if you made it into two sentences -- . . . alone. She stared . . .

Also -- delete "Even though".

thank you

You're welcome.

To fix this run-on sentence, you can use punctuation to separate it into two sentences. Here's the revised version:

"Even though Jane Falk, the protagonist, was upset at first after finding out that her husband had been killed in a carriage accident and went up to her room to grieve alone. She stared out the window and thought about all the freedom that she could have now that her husband is gone."

In the revised version, a full stop (or period) is placed after "grieve alone," indicating the end of the first sentence. Then, a new sentence begins with "She stared out the window." This helps provide clarity and improves readability.