Overwhelmed

Hi everyone! I'm new to MFP, weigh 143 and am looking to lose about 20lbs. I have a couple of medical conditions including rheumatoid arthritis which makes it difficult to exercise. My heights weight was 165 about 5-6 years ago when I was very sick and on many medications that cause weigh gain. As my health improved and medications were stopped the weight just fell off until I hit my current weight. I seem to have been stuck at this weight, although admittedly I haven't really dieted much. Many years ago, before I got sick I was about 120lbs, so I had been hoping the rest of the weight would melt off until I got there but it's been over a year now since I stopped losing. To add to the complications, I have exercise intolerance cause by a cardiovascular condition. And I can not participate in any weight bearing exercises on the order of my doctor.

I eat a mostly vegetarian diet with lots of beans, fruit and veg. I eat meat/fish once or twice a week max. I ride a recumbent bike for about 45 mins a few times a week. I feel utterly lost and hopeless that I will ever be skinny again.