Such a sad story 
I’m not really all that good with relationship advice, but I’ll try to give some good ones.
If you feel as though you like him and he likes you, like more than friends, then go for it! But, you should always keep in mind that if it doesn’t work out, then you may be losing your best friend. You have to chose whether you want to continue to be friends, or if you want to be lovers, possibly forever, possibly not. Because, I can tell you that coming back from a romantic relationship, to become friends again, is not easy and .ay even take therapy.
I hope that this helped, and good luck.