Pet Walker - Now Hiring

I seriously need help getting my male cat, whom is name Ginger, to not attack my female cat, Athena. Ever since he came back from the vet a couple of months ago from a UTI issue, Athena has been absolutely terrified of him- and with this ego boost, gave him the confidence to straight up attack the crap out of her whenever possible. This has caused me to keep her in my room 24/7. Im moving out of the house and currently cannot keep her, so shell have to stay with my dad (or else id have to give her up). I just need her and my other cat to get along so that she can atleast be a normal cat and roam around the house, because she deserves to.