can't eat more calories...

hello. the title says it all. i'm hardly ever hungry and i can't stand eating, but when i do eat it's always vegetables and such. i can't eat eggs and meats other than chicken or fish make me sick. i never gain weight, but i can't seem to lose it either, unless i exercise like a madwoman, which i can't do now because of health issues and stress on my joints. so is there anything i could do? maybe eat little stuff more often throughout the day?

my husband suggested splitting my meals up so that i have six small snacks a day throughout the day, but that doesn't seem to work either.