That's something no one really believed or cared about in the first place. The UK had never really cultivated any interest in building allies within the EU. Quite the contrary, they spent their time within the EU insulting MEPs or/and accusing the EU of everything.
Those who were traditionally pro UK (Malta, Holland etc) were shocked with the UK calling for a referendum on Brexit. They considered it as a catfight between the Tory party that got out of hand and a betrayal towards them and their combined interest. Once Brexit was won, these countries (now a minority) were quick to build alliances with others knowing that the UK won't be there for long.
In my opinion, the UK should have had the decency to start negotiations with a plan in mind and sufficient backup at home to implement it. The EU might not be the most flexible thing around but it does offer alot of different deals (EU Membership, EEA membership, Customs unions, Swiss like bilaterial agreements, a CETA like trade deal etc) which were tried and tested and were relatively easy for both parties to implement. Instead the UK went for a bold and new relationship (the EU calls it cherry picking), no one can really comprehend and which is heavily stacked towards the junior partner. That's a bit of a problem since it gave space for individual countries to come out with their own list that they want implemented. Its very difficult to come out with a deal which make 28 countries happy.