I don't want to hide it anymore, but how can i not?

I've been suffering from bulimia since the age of 16 maybe sooner idk.  I now will be turning 21 in a month or so.  Ive been married almost a year.  My husband knew when we were first getting together that I had been working on over coming my problem.  He made me feel normal and beautiful no matter what, hence why i married him :)... A couple months into our marriage i gained 10lbs putting me at a healthy-ish 132lbs, im 5'8.  I called it my comfort weight.  I HATED my comfort weight.  I couldn't look at myself in the mirror without feeling ashamed that i let myself gain the weight.   I couldn't binge and purge all the time now living w my husband so i have noticed that i just dont really eat anymore.  I always joked with my friends that i chose bulimia over anorexia because i do love food and could never starve myself .  Low and behold i can.  I make excuses on my lunch break that i don't eat because i don't like to be rushed when i eat and that i have to make food when i get home for my man anyway.  I eat only when my husband eats so not to draw attention.  In a couple months ive lost that 10 lbs plus another 6.  last time i checked.  i'm now 5'8 weighing 116.  i've lost my curves and that depresses me even more.  I feel so trapped inside my own head and body.  I feel sick if i eat a whole meal but luckily i never have to unless out to dinner then i just wait to get home, jump in the shower, and relieve myself of the "poison" i've put tin my body.  I'm so ashamed that i can't overcome this.  It's my body i should be able to control what and how much i eat, and be ok with it, but i can't.  And knowing that makes me feel like even more of a failure.  I want help, I just want to scream at the top of my lungs please please someone anyone save me.  Save me or kill me now because i know i'm killing myself slowly. I just don't want to let my parents or my husband feel guilty or responcible for me being like this.  I don't want to hurt anyone i love with my failure and mess up for letting it get this bad.  i find myself stuck.  please someone help me tell me what to do.