I have been with my husband for 4 years and his mother does not seem to care for me. There have been incidences where she has hurt my feelings and treated me as if I were not there and not part of the family. My husband has noticed this and asked her if she had a problem with me, but she responded "no".
How do I keep myself from disliking her? My husband is upset about this and is not sure what to do either.
You are lucky to have the support of your husband, and he has been willing to have talks with his mother. You, unfortunately, cannot say anything directly to her about her behavior because she will either ignore you or view you as interfering.
By hurting you, your mother-in-law is hurting her son, too. She does not respect him if she does not act respectful toward you. He should not have to cut off contact, but limit it if she refuses to cooperate.
Your husband needs to understand that support of you does not mean he is taking sides and does not diminish the love he has for his mother. But, it does mean that he will not allow disrespect toward his wife.
For now, being cordial, but keeping your distance, is often the best way to handle the situation. Keep the visits to a minimum. Do not invest any more emotional effort into trying to have a good relationship with your mother-in-law. It also helps to feel sorry for your mother-in-law because in the long run, the person she is really hurting is herself.
It would be beneficial for you and your husband to seek guidance from a marriage counselor. The counselor will be able to give you coping strategies and how best to deal with your mother-in-law.