Babe - I really hear you. I had a bulimia issue during my late teens and twenties and have maintained fairly strong body image issues ever since. My sister was a very successful model throughout this time and I felt such a need to be thin etc that it got out of hand. I was the same as you without hospitalisation but would make myself sick after most meals.
I had the same fear when I fell pregnant the first time (2004). Even though my bulimic tendencies had stopped years before, I also have "the switch" in my brain that turns on when I am scared about looking/feeling "fat" and putting on weight - not feeling "perfect".
I think if you are really worried about it, I would talk to someone - talk it through with a counsellor or your midwife/GP/OB - someone who will be keeping an eye on you medically during this time and can help support you through it. you need support and reminders that all will be well.
It's a very difficult thing when that switch is always there but you need to remember that the baby is the most important thing and needs you to eat healthily and regularly. That was the way I got over the concern. I put on 14 kgs first time and believe me, the 70kg barrier was a real hurdle for me! I finished up at 71kgs and the thought of getting back to my ideal weight terrified me. But, I got through it by reminding myself how unbelievably lucky I was to be pregnant in the first place and that it would be selfish of me to let my own issues hurt my baby in any way.
As time went on, I became more comfortable in my pregnant skin and had the support of DH and friends who knew my history. I ended up having a terrific and healthy pregnancy.
Do you know if your OB is a "weigher"? Some weigh you in at each appointment and some don't. Have a think about this in regards to your own frame of mind - mine didn't weigh and that worked really well for me, but you might be different. For people with our histories, those scales can be a real enemy in regards to pregnancy as the guidelines for weekly weight gain can fluctuate and cause you stress if you have gained what is thought "too much" in any given week.
I don't know if this will help you but feel free to ask me anything - I do know where your head is at and it's a scary thing. Look after yourself and that little baby!
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