Morning naturemum - your post could have been me when my son was aged 10 months (or in fact 18 months, or even recently until he went into his own bed )
First of all it is really normal for b/f co-sleeping babies to do this, and does not mean there is anything wrong with your son or the way you are caring for him. There is no need to change things if you are happy with feeding him in the night like this. However you sound as if you are becoming exhausted. I have two strategies to suggest - number 1, grit your teeth and stick it out. It will get better, worse, better, worse and eventually cease to be a problem. To do this you ideally need a supportive partner, a good supply of reassuring and encouraging books such as Dr Sears, Three in a Bed, and Our Babies Ourselves, and a sense of humour. You also need to go to bed EARLY, and nap whenever you can during the day.
The second option involves a gentle type of night weaning. I have not done it myself (too lazy, ultimately, you have to be fairly committed and consistent) but have two links and a book for you to try.
Changing the Sleep Pattern in the Family Bed - this is not recommended for babies under a year but could give you some advice - also, your baby will be a year old before you know it
Good old Dr Sears - he says "If you resent it, change it", and offers 12 night time alternatives to breastfeeding
and finally The No Cry Sleep Solution , a very gentle child-centred approach which works for b/f and co-sleeping babies.
It also occurred to me that you may be feeling like the odd one out among your friends etc. I found La Leche League meetings very helpful as many other people there will be making the same parenting choices as you, and struggling with the same problems. Also - DO NOT ASK YOUR HV FOR ADVICE. Unless you KNOW she is very sympathetic to lentil weaving types. Health professionals do not usually respect your choices if they involve co-sleeping and feeding to sleep rather than cry it out , and can leave you feeling very undermined and lacking in confidence
I hope any of this helps. Let us know how you get on, please.