never constantly connected

[#1]

It's not a simple speed problem as such, the speed tests i recently did were showing nothing startling, the sort of speeds I've always had. But the service is barely usable quite a lot of the time.
Now I'm prepared to be told that I'm really not understanding what is going on, but this is what it seems like to me:
The top indicator light on my router, the one marked 'internet', nowadays is NEVER constantly lit, it's always flashing. Up until the end of last year it would settle down to showing constantly green, now never.
I'm finding it near impossible to use certain websites, especially those [facebook is one] that require a fair bit of traffic in both directions before they will finish doing something apparently simple. Those kind of routines are always hanging, taking ages, or they simply fail and need to be triggered again. And again. And again. I can spend ten minutes trying to do something simple. This is deeply frustrating and I'm considering finding another provider, only I'd probably have the same standard BT line again anyway. I've got to the point where I'd happily pay for a service upgrade just to have some of these popular sites work again: except that I shouldn't have to do that, and it all used to work quite happily. The problem has just been getting worse over the last few months. There had been blips of service deterioration before but then the general level of service would improve again. Hoped that would happen again but it hasn't.
I'd probably blame BT but that doesn't get the problem fixed. I can blame facebook of course, but that's not the only troublesome destination.
Maybe there's a point i'm missing, but if the connection isn't constant then that seems consistent with the failure of anything that requires a constant stream of information in both directions. Even though I know that traffic is all in discrete packets anyway so you'd think that wouldn't matter.
this is driving me to distraction
thanks
Thomson TG585 v7
Mac on Snow Leopard
Current package - Extra
Bath Somerset

[#2]

Thanks for getting in touch.
With regards to your 'Internet' light, don't worry too much about that. The light will flash data is being used. The only lights that should stay stable are your Power Light and Broadband Light.
I've taken a look at your connection and can see that you either lose connection or switch your router off overnight, is this the case? I would high recommend ensuring that you leave your router on at all times.
If, with your router switched on you are continuing to experience drops, please connect your router into your <a href="http://www.plus.net/support/broadband/master-socket-guide.shtml#whatsTest">Test Socket</a> with an alternative <a href="http://www.plus.net/support/broadband/microfilters-how-and-why.shtml">Microfilter</a>.
Let me know if there is anything further  can help with.