If you received a party invite "Save the Date! You are Invited To An Event With Me!" then it's very probably malware. (I recently received this from a well-connected EMGW member's email) In my case, hovering on the invite link yields the domain endless-eviteonline. Evite actually only uses evite.com and evite.me.

From what I understand, the fake site asks you to log into your email through them to see the invite, thus capturing your credentials. It then uses these to impersonate you, opening you up to e-fraud. It also may send invites from your account to your contacts. 

If you signed into the site from such mail, please change your email password immediately, and secure any logins that use that email for login recovery/validation.