I agree with Spoiler.
I will answer a few questions, though, Sue.
If he has administrator password on your computer, he can read any file on your computer (with some exceptions).
So, after your notation:
1) Your example with which sites do you visit: he has read access to log files. Yes, he can check where have you been on the net, when. If the e-mail is not downloaded on your computer he needs the account name and password of your e-mail account, he has to log on on "your" mail server and read the e-mails. If you download e-mails to your computer he is not stopped from having a good lecture time (he has read rights, remember).
He can read ANY file on your computer (with a few exceptions that I'll note later).
2) N/A is not "network administrator". When the administrator is noted in your event viewer, he is noted as a casual user - he can be an administrator and not having to be named in the event viewer as administrator. His user account might be "Boo", member of Administrators group on that computer. When you will read the events, you will see Boo and not administrator, though Boo has administrator rights (I hope I don't confuse you).
N/A - means "no user" in your particular case. For example, on my computer, I have log messages from Avast!, where the source is Avast and the user is N/A. No user this means.
3) Talk with an ISP and require a new connection. Or as other forum colleagues said, talk with the same ISP and require a new connection. Connect your computer directly to their equipment.
Another way: buy a router. Connect your computer to that router, pay attention - set it up properly, pay attention at the administrator password, disable the "remote administration" for that router. Your ex should not have physical access to that router or he will be able to "reset" the router and change administrator password, change the settings.
It is not complicated to set up the router, but on a forum... You already owe me a big icecream
In fact it is very easy, but it would take at least half of hour to teach you how to do it (even if you read the user manual).
The last way: take a free firewall or buy a firewall (computer program) and set it up properly. You don't need much to know about how to set it up, the discussion is almost as the one regarding configuring routers (home routers, not routers in general). The degree of security is dictated by the degree of security of your computer. If he has administrator access to your computer he can do anything he likes on your computer.
4) N/A is not an user.
You can isolate your computer from the others by using a firewall or a home router (connect only your computer to the router, and your router connect to the "big" network).
5,6,7: you read the e-mail only on blackberry? On which server is located thepharmacy e-mail server? Your ex has administrative rights on this server? Here you have to give me a little more details.
Exceptions of files: files he can't read even if he has administrator password.
They are "passworded" files - doc files, excel files, archived files with password. There are others, but you don't use them (encrypted files). Though there are programs that can crack those passwords and he will be able to read the content. If you have pdf files with password: they are not protected, it is extremely easy to bypass the pdf file password.
Sue, please don't step into paranoia. Breath deep and either speak with an ISP for a new contract, or connect through router or with a firewall. Note: the internet transmissions are not encrypted in general. If you connect to his network he could watch your every move on the internet: what you send, what you talk, what you visit, when, EVERYTHING. But... Are you sure he has the means for this? (the time being the most important)
So, my recommendation: see who is member of administrator group on your computer. See if your computer is member of a domain (in this case the domain administrator can do many on your computer - I mean everything). Try to obtain a new internet connection from an ISP (internet service provider).
