We were once lucky enough to end up with two mares like this at one point. We threw them in together, yes there was a little scrap but they very quickly got over it.
If your nerves will handle it put her in with a bossy old mare that wont take any *****, barefoot preferably. IME mares make a hell of a lot of noise and drama but they are actually rubbish at really fighting.
Or keep her alone forever and she will become more anti social.