Sorry to hear that, wishing Neil a speedy and complete recovery.
Windsurfers must realize that
boaters may not know that windsurfers have the right of way. It is quite
possible that the boaters thought they were doing exactly what they were supposed to do when the accidents occurred, and that they though the windsurfer was at fault. Some of the blame can be assigned to the Department of Transportation. Check their "Boating Rules at a Glance" (
www.transport.wa.gov.au/mediaFiles/marine/MAC_B_BoatingRulesAtAGlance.pdf):

There is
nothing stating that sail boats and windsurfers have right of way in the brochure! The only mentioning of sail boats is in the overtaking section (".. the sailing boat must keep out of the way.."). The more detailed section at
www.transport.wa.gov.au/imarine/rules-of-the-road.asp also is marginally better in this regard, but you have to expand the "When power meets sail" section to see the actual rules.
I have actually seen an experienced windsurfing instructor insist that the "right before left" rule applies on the water. He happened to have an advanced (commercial) boating license, and did not fully understand the differences as they apply to "power meets sail" and "sail meets sail" situations, and was very surprised about the "starboard before port" and same-tack rules. So I would certainly expect a lot of boaters who never sailed or windsurfed to also not understand the right of way rules correctly!