Oh you poor thing, how horrible for you. I guess she's been a bit frantic running around organising the christening and now its aftermath and hasn't thought to contact you.
If I were in your position, I would probably make an announcement on fb about how shitty I was feeling due to having mastitis (provided I knew my friend could read it) and mentally give her a 'black mark'. Petty I know, but I can sense you perhaps frustrated and undervalued right now.