I know just what you mean.I have never done sport to a high level,but I was certainly quite fit when I was diagnosed.5 months after treatment,I felt like you are feeling now,but 12 months past chemo,as I am now,I feel really good,and pretty much back to normal.I am finding too,that the further you get past treatment,the less you worry or think about things like only having one boob,or what people say about you.And of course,as time goes on,people just say less.I suppose that no one knows what to say to someone that has had Cancer,so they just say what they probably think is right!!!Your question about how far to push yourself is a good one.I think that we definitely need to push ourselves ,because if we don't we will never get back to the way we were.The more we exercise,the better we feel.When I finished chemo,I was definitely more tired,my knees ached badly when I tried to ride my bike( but I rode it anyway) and after hard exercise,I was pretty much wrecked.I went to an exercise physio at RPA and I also did group classes with him.He used to push us( the other ladies had also had BC) to the max.I think this is when I realised that I was going to have to really give it my all,if I wanted to get back on top of things.I feel that after chemo,our mind knows what we should do,but our body finds it hard,as there are often posts from ladies that are struggling with their weight or fitness in general. If we can remember also,that staying healthy at a good weight,gives us the best long term prognosis with no recurrence,then this is another strong motivator.I am sure you will get on top,of things soon.Cheers xxRobyn