I have one female Jack in with 4 Jewels and after 3 months of everyone getting along great she's now chasing them and making a nest. Can they breed together or is she just wanting to mate? Do they go through the motions even when they're the only one of their breed?

some specie can fertilized eggs of other fish resulting to a crossbreed.
i am not sure if jewels are one among those specie that don't give a damn
whether the eggs came from their own kind or not, they just fertilized the
eggs...

I guess we'll find out soon then, she's getting more aggressive by the minute.

a female will go through "the motions" as you said even if alone in the tank. as for her breeding with jewels i wouldnt think it possible since jacks are central american and jewels are african. but im not 100% positive on this.

Will she stop in a week or so? My poor Jewels are getting stressed out but I don't have anywhere else to put them.