Her2 Question

I have been reading posts on this board of some time now and have learned a great deal from this site. What I have been wrestling with is my her2+++ status, basically I have been waiting for a recurrance or possibility that my neg sentinal node was wrong. My biopsy path report showed possible lymph invasion, so I am totally focused on that.
I met with rads onc yesterday to do the mapping before starting radation. I asked if I were to have radiation if I needed a mastectomy in the future would I be able to have implants. He was confused and stated that if I recurred then I would have another lumpectomy if caught early. He went on the say he didn't expect me to recur. Stating that I had a 3% chance of recurrance. I'm confused by this. I am Stage 1 Er-Pr-, Her2+++. Finished 4 cycles of A/C and went on Taxol for 12 weeks, started Herceptin with Taxol after 4 weeks into Taxol due to low Muga score (56% before A/C then 46% after). Started herceptin went Muga went to 53% and onc doesn't believe that I will be able to stay on herceptin for 1 year due to the decline in muga. Have been taking 100mg co-Q10 as directed by this site to improve heart function.
As I babble on what is exactly by stats for beating this? Most messages I read here have people who develop mets and go onto Stage IV. I really want to know what I should be focusing on, feel at this point I'm just waiting for bad things to happen. Anyone have any stats or recommendations on how to move on from this? My mother died 2 years ago after struggling with mets to her bones. She never knew she had mets or a recurrance from her bc dx 15 years prior. A bone broke and thats how she knew she had met to the bones. She only lived with the mets for 4 years, and it was a difficult 4 years. Don't want a repeat of this.
Any suggestions, thanks so much for listening and your support.
Rocky