God allowed your stroke to happen but that doesn't mean He necessarily caused it. Many things happen to us that we'll never fully understand this side of heaven, and we can only turn to God and trust Him to bring good out of them. I pray this will be true for you.
It isn't necessarily wrong to ask God why He allowed something bad to happen to us; sometimes He wants to teach us lessons we need to learn. For example, if we have been neglecting our health and have a serious problem as a result, then God wants to teach us to take better care of ourselves in the future.
But the real question we ought to ask when something goes wrong isn't why it happened, but how God wants us to respond. That should be your question as well, because God doesn't want you to spend all your time thinking about the past or complaining about all the things you can't do. All that does is make you (and those around you) more miserable.
Instead, He wants you to turn to Him and ask Him how to make the most of your life right now. Begin by thanking Him for sparing your life; the Bible says, "Give thanks in all circumstances, for this is God's will for you in Christ Jesus" (1 Thessalonians 5:18). Then ask Him to help you adjust to your new situation, and to show you ways you can serve Him right now.