I am sorry you are finding this. My exwh used to hack into my emails as well. I found the same thing an email deleted. But I tricked him into admitting via email he was hacking into my emails, just in case I ever need it for court. My exwh is a computer tech I would go out and buy a new laptop/computer if you can afford too just to be sure or if you are tech savvy reset it to the original factory settings or take it to a professional to do.
Funny thing is my exwh promised me he would still look after my computers I would sooner pay someone else to do it. Goodluck.