To add onto the comments, have your husband take Garlic pills daily. They are a good probiotic and they are cheap. They will help to treat and to get rid of his yeast infections so that he cannot pass them onto you.
it sounds like you could definitely be getting it from your partner, (and men can get thrush) so perhaps he needs a treatment - you can get oral capsules from the doctor and topical applications from the pharmacist. As diabetics are more prone to yeast infections, perhaps you could use condoms in the meantime and see what happens.. Condoms are the greatest thing in the world, but i definitely think they are preferable to yeast infections lol
good luck :) Make sure you go to the toilet straight after sex too.... sometimes that helps in reducing the incidence of UTI's and cystitis so might be worth a try.
I'm sorry this is happening to you. There are things you can do to help yourself. Try a really good probiotic (they aren't cheap, expect to spend $30-60/bottle) and keep it refrigerated. Also, boric acid capsules can be inserted vaginally to help restore the normal vaginal acidity. Your pharmacist can make the boric acid capsules for you. Boric acid is poisonous if you swallow it so don't leave these out where kids or pets can get them and don't forget what they are and swallow them yourself. You should also give your husband a good probiotic and help him really keep his sugar in check. The less yeast he has the less yeast you will have. Also, I find that during the week before my period starts I am much more prone to yeast infections and of course if I eat a lot of sugar or drink several glasses (sometimes just 1) of wine. It takes a lot of monitoring! Good luck!