I faced this. Start a website then lose it because I would be losing interest in few weeks.
The thing which I followed is to fix my routine. Joined a Gym, it helped a lot on focusing on things & made me mentally strong.
Take off time, started travelling & took a long break & then get back to work. A step closer to nature made me fresh & met people who are really working hard despite the lack of resources. This made me think about how am wasting my time, despite having all the resources.
Sat one day & written everything on things I wanted to do. Made a weekly task, monthly, quarterly. Then started steps to accomplish it.
At first it wasn't easy but slowly I made a habit & then finally get used to it.
Just follow something for 21 days, it will be a habit.
All you need is 21 days.