Friendship

1. make friends

2. strike up a friendship

3. form/develop a friendship

4. a friendship grows

5. close/special friend

6. a casual acquaintance

7. have a good relationship with someone

8. keep in contact

9. More than friends

9.1. to fell madly in love with

9.2. a love at first sight

9.3. the love of my life

9.4. a love can be returned

9.5. to make a commitment

9.6. to accept somebody's proposal

9.7. to love each othe unconditionally

9.8. to have an affair