There are a few ways for this problem to be solved. First of all, make sure there are no mods that interfere with gameplay. If that doesnt work, you can try running the game as an administrator and running the game with Windows 7 or Windows XP compatibility. Finally, make sure all your GTA settings are fine and the problem doesnt come from there. What worked for me was removing CLEO, as it had several mods that interfered with how the game worked, and I removed all of them.
I'm pretty sure there are several mouse fix patches on the world wide web that solve this problem without too much hassle or digging into your game settings. Luckily the problem of the help requiring person is solved and therefore we will lock and archive this post.