hudi – Admittedly I did not read all the comments (only some), so it could be that I am repeating what someone else already said. Here is my opinion.
In today’s fast pace stressful world, a world that is both fragile and often without mentors to guide us, it is common place for many people to seek psychologists and psychiatrists. These doctors used to be referred to as “quacks” in my youth. The reason they were called that was because the only people that needed their services were people that were severely disturbed. Nowadays, many healthy people require their services and it is not as embarrassing to admit going to a psychologists or psychiatrists as in the old days. Many many people go today and anxiety is ranked as the 7th top psychological disorder in the US (I just looked it up). In general, I was surprised to learn that 1 in 5 adults today are treated every year for psychological disorders (just looked that up as well). Thus, if a person is being treated for anxiety it is not necessarily a “Red Flag”.
However, with that said, there are several things for you need to clarify and consider before going out with someone on psychotic medications.
1) What is the reason he is on Anxiety medication? Is he presently dealing with high stress issues or does he have a mental disorder? If the latter you need to know what and how sever.
2) How does he act when not on medication?
3) If he has a mental disorder what are the potential impacts it can have on your relationship if you get married? Can you live with those impacts?
4) Is he only going to a psychiatrists or is he also going to a psychologists? If he only has a short term anxiety issue then he does not necessarily need a psychologists. However, depending on the issue, if he suffers chronic anxiety he should be seeing a psychologists as well. If he is not, it may be wise to reconsider going out with him.
Note: It is incorrect to rely on advice and opinions of Shadchanim. They have self interests that can cloud their perspective in these matters. You need to consult with a 3rd party, someone wise and experienced in these matters and discuss it with him/her. Best if you can consult with someone who knows you personally and who takes an interest in your well being. It is also wise to consult with a professional psychiatrists or psychologists to discuss the ramifications of living with someone with his types of issues.
It is good that you are not taking the issue lightly and seeking advice. May Hashem help you get the right advise and help you make the right decision in this matter.