Some points that seem fairly obvious to me
Scotland cannot leave the UK before the UK leaves the EU. Even if Scotland voted to leave the UK tomorrow, there would still have to be a negotiation similar to the negotiation we haven't quite started yet with the EU. There's no way the UK government is going to even consider negotiating Scottish independence before we're done with the EU, it would be too much to handle at once.
Theresa May will never let the Scots have independence while she is prime minister. Conservatives are pretty much all unionists. To go against that will make her career toast.
If Brexit goes ahead, I think eventual Scottish independence is inevitable. It's just another way in which the Brexiteers have kicked us all in the goolies.