I don't have much advice to offer, but wanted to say that I occasionally ride with a guy who had a stroke. He's about 39 or so, and had a stroke when he was 32. I've never talked with him much about how he was able to get back on a bike, but he was - both road and mountain. Prior to his stroke he was apparently an extremely competitive racer. I believe it took him years to be able to ride again but he was determined.
He has difficulty clipping into his pedals - yes he still uses clipless for both road and mtb - and he sometimes has trouble shifting on his bad side. Things like changing a flat are challenging for him as well. Not much else I can offer, just an example of someone who was able to get back to riding a traditional bicycle. Obviously every person is different - best of luck.