I'm a vegetarian and I keep getting thinner?

I've been a vegetarian for a year now, and I love it. I feel so much better about myself. I am not using this as a diet method, but just because I am strongly against animal cruelty and it's just healthier. Anyway, the problem is I keep losing weight and I don't want to. I was around 140 last year and I'm almost at 110 lbs right now, I just don't know how to not lose weight anymore. I eat so much fruit and veggies, and lots of protein which should be helping me. If someone is vegetarian and is going through the same thing, please help!