I over endulge when I drink alcohol and feel extremely guilty about it the next day

Thank you for writing in with this important question.  There are some key words in your question that indicate you may have a problem; they are, "over indulge," "feel really guilty," and "angry drunk."  You also indicate that you have been unfaithful in your relationship while under the influence of alcohol.  In assessing whether or not someone has a "problem" with alcohol, some of the criteria I consider are whether or not they have attempted to cut back on their drinking and have been unable to do so and do they continue to drink despite knowing of likely consequences to their own emotional/physical health, relationships, occupational and/or social functioning.  

I indicated you "may" have problem because it would be improper for me to make a formal diagnosis over this type of forum with so little information; however, with the information you provided, my answer is yes, you may have a problem based on my interpretation that you have tried to control your drinking and have been unsuccessful and have continued to drink despite experiencing yourself as an "angry" drunk, feeling guilty after a night of drinking and being unfaithful in your relationship.  I would recommend that you see a counselor for a proper assessment.  I applaud you for being concerned about this issue and seeking help.