The short answer is that you will need to show a material change in circumstances warranting a modification of alimony. Just because your ex's income has gone up does not mean that you are entitled to a modification, nor the fact that things cost more. It will also depend on the language of your Agreement or Judgment regarding possible future modification of alimony, as well as increasing costs, etc. You will at the very least have to prepare a new matrimonial Case Information Statement and submit it, together with the CIS from the original divorce, showing that your expenses have increased, what your income is, etc. I suggest that you speak with a matrimonial attorney about the basis for an increase in your alimony.
NOTE: This answer is made is for advisory and/or educational purposes only. By using or participating in this site, or posting a question and obtaining an answer, you understand that no attorney-client relationship is being established between you and the answering attorney, and there is no attorney-client privilege between you and the attorney. You should consult with a licensed professional attorney in your state. The law changes frequently and varies from state to state. The information provided in this answer is designed to be general in nature and is based on the facts stated in your question, and might change based on further information.
A weekly guide with tips and legal advice for each stage of the process.