My Mail Inbox Being Accessed !? - Workstation E-mail & GroupWise WebAccess

We have GroupWise WebAccess which we can logon to our webmail from any Internet enabled computers with Internet Explorer. I need some opinions urgently, please help.

Recently I suspect that someone may found my password, no matter by what means, I've changed password regularly too, it could even be my partner (trust!)!

I use my e-mail at work, and that's not webmail of GroupWise WebAccess, I use it from my workstation, and I have these questions (I am a user, not an administrator or someone in company's IT department):

- E-mail are probably read by someone (through GroupWise WebAccess) after I've opened them, if thats the case will the person that sent e-mail to me get another read receipt?

- Is there a counter to count how many times the messages (Inbox / Outbox) have been read?

- I sent out some messages (at my workstation not on webmail of course) and I suspect that they have been read after my recipient read it, anyway to find out?

Any other suggestions on how I can find out if someone read my messages without having to talk to administrator or I.T department. I suspect it could be my partner and if that's the case, things could get real ugly in the family, and also with the kids that we have.

Thank you experts!