Please help! Methadone and anxiety!

First and foremost, before you judge me, please hear me out.  I grew up in a VERY dysfunctional family with most members either being drug addicts or in prison or possibly both.  I never really had a good support system growing up and pretty much grew up by myself after the age of fifteen.  Anyway, at about 19 my friend had a major surgery and gave me a few of her percecets.  They helped with my ever increasing anxiety and also helped me to forget my depressing family situation.  I took them with her for a few months and before I knew it I was suffering from nasty withdrawl (withdrawal) symptoms.  After that, I just had to find opiates to feel normal.  After trying to quit for a whole year cold turkey and contemplating suicide when the withdrawl (withdrawal) was at its worst, I decided methadone would be better than death.  So I have been on methadone for the past 5 years and have gotten my life on track.  I dont do ANY drugs, inlcluding alcohol and I have passed every drug test at my clinic since my admission date.  I have straight A's at a university and was recently inducted into the honors society.  I have a great home and a wonderful fiance.  I made a very poor decision to start using opiates in the first place but I have done everything in my power to get my life turned around.  Anyway, I have SEVERE anxiety that is really starting to effect my school work and social life.  I am constantly anxious and my heart is always racing.  This has been going on since I was a late teen but it keeps getting worse and worse.  Because I am on methadone every doctor thinks that I am just trying to get drugs.  I cant really blame the doctors but I genuinely have uncontrollable anxiety and I need medication.  I have tried zoloft, effexor and wellbutrin with no positive effects on my anxiety.  Are there any other options for me???  Can I do anything to convince the doctors I am not lying I actually have horrible anxiety.  I am so desperate and this is really starting to ruin my life.  Any advice would be highly appreciated.  Take care and god bless.