Loan to a family member

Well my Ex-Step-Father was about to lose his house if he didn't pay off payments for 3 months. This man has been the only father figure in my life for 15 years. He gave me a car as collateral, I could sell the car for about $17,500 and I gave him $8,500 to pay his bills. He said he would pay my back in a 'couple month's' after he finshed a couple big jobs he had lined up (construction). On Oct. 14th it will be 6 months I have had this car and he hasn't spoken to me. I've tried calling, stopping by his house, texting with no response. So the only contact I have with updates about him is through my Mother who he talks to daily. She is also the one who asked if I would loan him the money. Well everytime I bring it up she says that all he talks about is paying me back and how embarrassed he is that he had to borrow money from his daughter and such and such. Then why cant the man call me back?!? I recently found out I am pregnant with my second and I really could use my money back. So I either sell the car myself and not give him anything and deal with his tantrums and end up losing the only father figure in my life or I wait and sit on this damn car and hope that he pays me back or even calls me for that matter. I'm so conflicted, I really need my garage, I really need my money back, and I mostly need this to stop being a stressor on my relationship. It is starting to cause alot of problems between my fiance and I, even though he agreed with my helping in the beginning.

Edit/Update:

Thank you for your opinions ladies. I do have the title and had already put it in my name. The car was completely paid off. The reason he didnt sell it was because he remodeled the car himself, its a '70 camero, he put a brand new engine in it, along with nos, new tires and suspension, new paint, new upholstery, everything and its his baby. Thats another reason why I thought I would get my money back because the car means alot to him. I contacted my Mother after trying to call him again and told her he has until the end of the week to contact me and then I will give him a month to start payments at least. If I dont see any money from him then I will be puting the car up for sale. Again thank you for your input ladies I needed to know I was doing the right thing in drawing this to a close.