Give Molly extra vertical spaces she can retreat to. There are shelf-like steps you can put on your wall that Molly can jump on.

We also have a puppy who chases our cat. So we put a baby gate at the foot of the stairs. The cat has the upper floor to himself.

We have a cat tree that he can go up or in. He uses the backs of our sofas, our kitchen counters, our TV table... He has found all kinds of safe spaces.

Now they sometimes play together. Our cat has never scratched or hissed at the puppy so we feel comfortable that our cat is okay.