Tictac - you said you intend to feed for eight weeks - I assume that means you have a baby of less than that age.
I set myself goals with bfing in the early months and it helped - my first was six weeks then 12 then 6 months and then a year. After that I went with the flow and found myself giving approx 1 feed every other day to a 2.5 year old. I don't think any first time mum goes into bfing thinking 2.5 years.
But it's a gradual thing - he didn't suddenly become 2.5, nor could I imagine him at 2.5 when he was a tiny baby.
I still can't imagine how I am going to cope the first time he comes home drunk, but I know I'll be okay because he will gradually become a teenager, I won't suddenly have to deal with teenageness from nothing.
What's the point at getting really good at something (it took me about 8 weeks) in order to stop? I watched a few women get to grips with bfing and then spend a further 8 weeks struggling with bottles, by which time they were struggling with puree.