Hi Joanna03279, welcome to Psych Central!
It sounds as though, if you stayed, your partner (and your family) wouldn't be that much of a relief from depression. Will you have access to counseling or therapy?

Here's a page about things to keep in mind when leaving an abusive relationship. I wanted to mention it because conventional wisdom, at least, warns that abusive partners often become even more dangerous when they find out that their partner is leaving. Here's where that link came from. Those particular sites seem to focus on California; if you're in another part of the world, I hope you find other appropriate resources closer to you.

Good luck!