I’m BPD and sometimes I feel I’ve caused his depressions. 
When I’m depressed I go through the typical needy and rejection-fearful mode. When he is depressed he goes into hardcore isolation mode. It’s not clicking well and we are getting more and more depressed and exhausted everyday. 
We don’t really have friends (he has some but he likes to keep his distance and privacy with them, I have none). Due to money and work we don’t really have any free time or resources for hobbies. 

Any advice on how to deal with a relationship where both are depressed (and one has BPD)?