Been there a few times. Try and have a plan for each day, something to look forward to...good tv prog, good food, phone call to a friend/family, walk in the sun, good book etc. Write a treat down in a diary so there is something on each day, no matter how small.
Take one day at a time, live in that day, don't worry about future.
Plan your weekends...cinema, meet friend/s, a meal out, shopping and coffee, gym, swimming, long walks etc.
Plan future...a holiday, weekend away, start a new pastime, go to a class in the evenings, plan days out in the summer, see what's coming up at the theatre, buy tickets for a gig, buy a bike etc.
Change your furniture around, get new clothes and/or bedding, redecorate, buy houseplants...anything to mark out a new life.
Basically keep busy, it's ok to have times when you won't want to do anything or go out...play music, watch tv, a long bath with an early night in clean bed clothes, pamper yourself etc.
What helped me was buying a book full of puzzles which kept my mind occupied for chunks of time. A friend bought an intricate colouring book to do the same.
One day you will realise you have built a new life and turned a corner. It will happen. In the meantime keep your mind focussed on you and the things you enjoy.