Some good suggestions on here already for not having to spend time with a neighbour who is clearly upsetting you. However you go about it you need to be able to relax in your own home. Could a friend or your husband help next time she knocks, calls out or tries to give unwanted gifts? I really do think you may end up having to be a bit more assertive and telling her you are not available for visits, do not want to go round hers for coffee etc.
I agree with Starlady that "The racist comments would be a total deal-breaker for me". That she is racist about your husband could be the number one reason to avoid her - just tell her once "I cannot be friends with a racist" and walk off. She may not like being told this, but you don't like having a "mildly racist" neighbour insult the man you have been married to for 33 years. You and your husband should not have to tolerate any racist behaviour (nor should anybody else), it is unacceptable and hurtful.
If she has the hide of a rhino and fails to get the message if you cut her off, don't invite her in or accept invitations, and call her out on being a racist, tell her your mental health makes you want to tell people to F**k off and leave you alone!
Good luck, I hope you find strategy that works for you and that you get some peace back in your life, can enjoy your home and ease some of the stress to lessen your chronic depression. 
So it begins….. Streeting resigns



