Hello, I've Had Severe Stomach Problems For Almost A Year

Hello, I've had severe stomach problems for almost a year now and I've been diagnosed with gastritis but the problem is I don't eat any fruits or veggies not even one of each ... Ever since I was a little girl .. I have tried them all but I can't seem to come to like them or better yet get them down my throat do you have any advice for me I lost so much weight and I'm unhappy