1. an acquaintance childhood friend. 2. a workmate. 3. a fair-weather friend. 4. a friend of a friend. 5. a family friend.
B stay in touch - to maintain contact with another person
catching up on - to learn about
love-hate relationship - strong feelings of both love and hatred for someone
get on well - to be in a good relationship
when the going gets tough - when conditions become difficult
stick up for - to support or defend someone (something)
bump into - to meet someone you know when you have not planned to meet
picked me up - to get or bring someone or something from somewhere
С 1. catch up, 2. when the going gets tough, 3. pick you up, 4. stick up for me, 5. get on well, 6. stayed in touch, 7. bumped into, 8. love-hate relationship
Есть совсем небольшие сомнения, что 5 и 6 можо поменять местами, но это уж очень небольшие сомнения