I will just throw out some thoughts here since I have no medical background. But, I did learn that a lack of vitamin C can cause a person to bruise easily. Since your mother is not eating properly, it may help to get some orange juice in her diet.
Another thing that works are those protein drinks. Some are chock full of vitamins. I bought one from the health food store called Spiruleina and would mix it with boost or ensure and a banana. That was full of good vitamins and (as we know) nutrition does heal. If you can get a glass down her, then it takes the pressure off of her eating the junk food all day... You will know she got her daily vitamins.
These are just a few thoughts and it certainly might just help that bruising problem... Try it and keep an eye on her. I know it helped heal Dad's bedsore that he had when he last came back from the hospital.
Wishing you good luck on this. I know how scary blood thinners can be. But, it is better than blood clots....
Love and Hugs from Glenda