I'm so sorry, OP, what a horrible situation to be in.
I can totally understand why you feel you need 'closure' but I wonder if that will actually do you more harm in the long run?
He's an adult, he owes you money and, whatever excuses there could possibly be, put yourself in his position - all of it. If you were in hospital, you'd find somebody to get a message to him, you'd do whatever it took to make sure that he knew you were ok and that you were thinking of him, that he was important.
If - and I know you wouldn't do this but IF - you decided to just dump and run, you'd plan it that a) you wouldn't send an 'I Love you' text, because you're not a sadist and b) you'd get that £200 sent to him by Special Delivery or through the letterbox with a note just saying "Sorry, it's not going anywhere, thanks for the nice times... blah blah".
If you go and visit him, you'll be all buoyed up in the meantime with a 'plan of action' and that will see you through but you're going to be totally flat afterwards when it comes to nothing. He is blanking you, for whatever reason. He's cruel and I don't know what depths he would plumb as he's already pretty low. If he's there and sees you - what could he say to you to soothe you or make you feel any better about yourself? If he's there and won't see you, you'll feel humiliated. There's no going back from what he's done, you'd never trust him or feel at ease with him again and why should you?
Grieve now and give yourself a date to stop crying over him, to get everything he's ever given you away or put in the bin. Write off that £200; you won't get it back. Chalk it up to experience and know that he is the one who has lost out, not you. He knows your a single mum and he took that money from you; that's pretty bad but to not pay it back - that's horrendous. You're so well rid of him, OP and I wouldn't pay for a drop of petrol to go and see him; he's the one who has been out of contact, not you. He's dropped you and he's a fool. You'll be fine, stay away from him and chat here, see you friends, don't run after him because you'll feel worse directly.