lilupix - sorry if you have read the info. on kellymom.com already about distractable babies, bf "strikes", etc., if not it will answer most of your questions as it always answers mine !!
My DS is now 18 months old and still bf 4 - 5 times a day despite that fact that he is super-charged and has been very very alert from the minute he was born !! He has been coming on and off the breast to look around since he was about 5 months old. But I make sure he is fed in his favourite place (his semi-dark bedroom) holding his favourite thing, his teddy, and that way he usually pays enough attention to get a good feed !!
Babies that drink less and less breastmilk after 6 months are usually being overfed on solids and snacks. kellymom.com recommends bf BEFORE breakfast, lunch and dinner. That way you make sure they have a good milk feed before they are too full.
I agree, most babies love to have a good feed just before sleep. I think that your HV has given bad advice for a bf baby. Why stop the night time feed when she enjoys it so much plus gets most of her breast milk at this time ? Most importantly, you enjoy it too and it does not disrupt your life. I think your HV's advice is a sure way of weaning off the breast altogether.
Also to reassure you further, according to bf experts like LLL, etc. it is extremely unusual for a bf baby to self-wean under the age of 12 months. I don't think your dd is sending messages that she wants to wean. There are other more likely explantions: a temp. feeding strike due to teething, thrush, over-feeding solids, and many more, etc.
Best of luck !!