Ex doesnt know I can see but he is still checkin the email add i set up 4 our talks int he past.Why?

My ex dumped me while pregnant,long story, ugly terms. Hehas been an emotional abuser for 4 years, with deep seated problems ( abused as a child, now still living with his mum at 29, drink, mayb edrugs, liesetc).He dumped me but I gained the upper hand by not reacting with shock and hurt as before, but with a fed up indifferent 'whatever I'm gone too cya'. He doesnt know I can see but he is still checkin the email addie I had set up yrs ago for our communication( he usually doesntuse internet). Why is he doing it?