Basically 3 possibilities:
a) your computer is compromised.
b) her comptuer is compromised.
c) someone somewhere between the two is accessing emails between the two of you. Could be at your ISP or could be her hotmail account or ...
Galaxy Note 8 vs iPhone X
5 best 3D model websites
iPhone 8 vs iPhone X
WhatsApp : comment lire vos messages sans que l’expéditeur le sache