I haven't played GW, but keep something in mind: a bunch of stuff (most of it actually) is modeled/rendered on the client side; the server only sends you updates about stuff, e.g. perhaps new monsters spawning in your neighbourhood, other players, etc. But most of the environment is most likely modeled on your machine. So even if your network connection dies, you will still be able to do some stuff, namely anything that doesn't involve the server.

That was the explanation for the apparently "partial connection" you were experiencing.

Now as for the actual problem, hard to say. Do a checkup of your system to see if you have any spyware or malware.
Are you using a firewall ? Check its logs, see if it reports anything that might seem weird.

The problems may be related to your router (if you have one), or your ISP. Do you lose connection when just surfing around the net ? Check with your ISP to see if they have been experiencing service interruptions or some such.

Until you localize the problem, it's hard to figure out what the solution is.