It might sound flippant but new psychedelic therapies are showing tremendous promise in treating chronic mental illnesses that are resistant to traditional psychotherapy/anti-depressants/anxiolytics. Rather than simply damping down negative emotions and thought patterns psychedelic therapy offers the opportunity for a 'mental reset', meaning a few treatments can result in significant improvements that last months and years.

The lay explanation of how they work is they cause a significant temporary increase in neuro-plasticity at the same time as creating a strong euphoric/anxiolytic effect combined with ego dimishment which allows you to consciously work through your issues and make a lot of (semi-)permanent changes in how you feel about things. of course in reality its much more complicated and a lot of the mechanisms aren't properly understood yet.

MDMA therapy has shown great promise in treating PTSD (is by far the most promising alternative to traditional therapy), and there's currently trials in treating terminally ill people with end of life anxiety.

Ayahuasca has shown great results in treating chronic addiction, and there's good reason to think its effective in depression and anxiety disorders.

LSD and Psilocybin have both been proven effective in treating anxiety in the terminally ill cancer patients.

There's ongoing clincial trials and new ones are started all the time so keep an eye out if you're interested in a new form of therapy.

http://www.maps.org/participate/participate-in-research

Unfortunately you're only likely to be accepted for a clinical trial if you meet pretty specific sets of criteria so this might not be a viable option for you. If you're truly desperate it might be worth travelling to South America for an Ayahusaca experience. Of course its a lot less tightly regulated than the clinical trials in the US but there are reputable providers around. As always make sure to do your research, and good luck.