Trying to loose weight before conceiving

I weight 240 I’ve had 3 miscarriages this past one was in august, I took baby aspirin and progesterone suppositories and miscarried at around 6 weeks. My doctor said he wants me to walk and drink water before trying again even though he says my weight has nothing to do with miscarrying. I’m on Mila birth control until I can try to loose weight how can I get motivated to loose weight? I have no motivation at all I want to be super healthy before trying again because when I do get pregnant again I have to inject myself lovenax every day and take 2 baby aspirin daily. Any recommendations?