knee injury and excercise

hi :)

so i have jumpers knee aka patellar tendonitis (had it for the past 6 months) and i recently learned it wont go away anytime soon. bummer! and i really wanna lose weight in a healthy way without injuring myself more. i heard it gets worse easily over time. any1 else who had it and was successfully able to lose weight? im doing easy streches, crunches, and anythign that wont stress my joints out anymore. im trying to eat healthy too XD. some1 please tell me i will be able to work around my injury and reach my goals. i really need motivation. thanks!