You can try apologizing. If that doesn't work, you will be left with running on your own and racing unattached at all-comer type meets. You won't be able to run HS races "unattached", as tempting as that might be.
If you decide to transfer, be sure to check the state's rules permitting subsequent competition. Some states ban kids from competing for a full year after a mid-year transfer, but allow immediate eligibility if they transfer during the summer. I don't know how easily it is to transfer either - will you need to move into the neighboring district? or can you just apply to transfer in?
One other thought - what is the rule for competing if you are home schooled? In our state, you can compete for any school within your neighborhood's district. If both schools are within the district, you'd be okay to run for either.
Each state has different rules and I don't think they are very consistent. I know a kid (not a good athlete) who competed for our tiny school, then transferred to the big public school - did not even try to compete there - and then transferred back at the end of the year --- and she had to sit out an entire year plus and never got to compete again. Other kids have transferred from public schools to private mid-year and gotten to compete. So, you'd better check that out. Another kid had been home-schooled and practiced with a team she thought was within her district - it wasn't and the school that was in her district complained and she had to sit out a year (ultimately moving and transferring to a different district altogether) I had a kid who was home schooled his last year and still competed for us because our school was within the attendance boundaries where he lived (along with 2-3 other schools, some of which were closer).
Good luck. Having a poor coach (if he really is a poor coach) sucks, but if you stick with it, you'll have other races later in life.