Hamilton was the ladies man. He was. Lin has an entire song about this part of Hamilton.

Here's some information on a couple of his girlfriends (pre-Eliza of course).

Hamilton met Cornelia Lott, later Cornelia Sands, the winter of 1779. By January 1780, Hamilton was completely infatuated with her. Colonel Samuel Webb wrote a verse teasing Hamilton: "Now [Hamilton] feels the inexorable dart / And yields Cornelia all his heart!"

In that same month, he moved on to a lady named Polly. Could not find any information on her because no surname was given.

Of course, that following February, Hamilton met Eliza so all was well.

Facts found in Chernow's Alexander Hamilton (p128)