Dear KLH:
I am guessing that your anxiety and depression existed before your later in life relationship, simply because many of us suffer anxiety and depression early in life, in our very first or second decade of life. Problem is that at this point, this relationship is elevating your anxiety and depression, therefore, it makes sense that you end the relationship.
If you attend psychotherapy and/ or feel way better at some time in the future, maybe then you can think about contacting him. But for now, you are experiencing severe distress in the context of this relationship- better then to not be in that relationship.
If you want to share more about this relationship, about your life otherwise, past and present, anything at all that you think may be relevant, please do, and I will read and reply to you further.
anita