When you read the article, it becomes immediately clear that he needs support a women's breast cancer group cannot provide.
He speaks of his shock, horror and shame at being diagnosed with what is commonly thought of as a women's illness.
He speaks specifically not about the cancer diagnosis per se being the shocking thing, but that he had breast cancer and about his fears that other men might doubt his masculinity and his manhood.
That is a markedly different reaction from the one women have to this diagnosis and needs a response that can adequately explore and address his emotional and mental needs.
As nowhere in the article is there even a hint of him being treated unkindly (beyond the fact that he was not kindly included in women's breast cancer support groups), there is no justification to assign blame to the women who rejected him (he approached several).
As pp pointed out, the women running the groups most likely told him about support dedicated to male breast cancer sufferers. And probably with sympathy and kindness - he does not claim otherwise.
A women's support group cannot and should not be expected to take care of the particular emotional needs arising from a breast cancer sufferer being male. That's why men founded support groups for male sufferers.
The article would have been much better and much more helpful, had the journalist bothered to explain this and then signposted other male sufferers to the specific support provided for them. It must be a common experience for men diagnosed with breast cancer to not know where to find support. Which is why I don't mind at all this poor man speaking out about this, it is a horrible disease after all, but the journalist missed an opportunity here to do some good with the story.