Hi Picture - yes I had the whole caboodle like you are having and it looks a pretty long haul when you are at the start, - I think I had quite a few wobbles too 
But it is doable - try not to look too far ahead and deal with each bit as it comes. Herceptin is not too bad - its not like conventional chemo, -it does have some side effects but they are very manageable and you can continue with life as normal when you are on it.
I think the things that helped me cope were firstly thinking 'good, they are throwing everything they've got at the bastard'
and secondly trying to take each day as it comes - I knew that my treatment was going to take two years from start to end of herceptin (yours might be shorter because I think they run herceptin concurrently with chemo now and I had a lot of delays and buggering about with my ops ) so I sort of resigned myself to getting through that time period, and making the most of days when I felt well and resting on the days I felt a bit crap.
You will get there my lovely
I'm still on tamoxifen, and I don't really notice any side effects now - you get some hot flushes etc when you first start it, but they settle down.
You will get teary days - we all do - I get them even now, and thats OK - a very shit thing has happened to you, and you need to go with your emotions, be kind to yourself when you are feeling down, have some treats ready to cheer yourself up, and plan something nice for when you feel well enough - even if its just coffee with a friend or a day out somewhere.
And you are half way through your chemo so you are doing well - you're on the home stretch now
and honestly chemo/steroids make you feel miserable and down once that is finished your body will start recovering, and you'll start to feel 'normal' again. xx
Happy birthday dear LittleNed - what a big boy! - I can't believe it, have fun at legoland 