In the first season Rebecca's dream ghost, that looked just like Dr. Akopian, told her that love comes in many forms, and it can be a passion. One of the things the show has subtly displayed is that Rebecca has been relentlessly pursuing things, but usually either her job or a boyfriend. So we know Rebecca fell in love in college and when that fell apart, she was unable to continue there, and after some hospitalization, she ended up at a different high powered institution. Then she ended up at a high powered law firm where she had done well enough to make partner even though the idea of being partner gave her a panic attack. So, she runs into Josh, upends her life to move across the country and be a lawyer at a much less high powered firm, but where she will have time to pursue to the fullest extent possible, Josh. And when the Josh thing didn't work, she then ended up with Nathan (and I know that Greg was in there too, and I'm not forgetting him, but she wasn't done with the Josh dream during the Greg phase). And then she realized she was repeating patterns, trying to micromanage and level up their relationship by granting him the dream sibling he didn't know he had (because he didn't). And when she realized that was a bad pattern she ended things with him. She tried working for Valencia, but was unable to do that without butting into client's lives, so she decides it's time to go back to work. Only she had forgotten that she had quit (or her mom had quit for her while drugging her, which was a nice nod to continuity, a lot of shows would have skimmed over that while we all wondered if she was using FMLA or what). So, then she enacts a plan to get the firm back from Nathan. (Who then continues to work there. It is still a TV show.) But then she and Nathan resume the sexual part of their relationship which Rebecca decides is totally not the same as her repeating old patterns.
All of this is to say that a lot of shows about working women do that great at her job, terrible with feelings thing. She's a tough boss at work, but her home life is out of control. And in this case Rebecca is, well, she's clearly a very good lawyer, but there's something to be examined in that she's in a profession where thinking creatively about the truth and manipulating people are lauded skills. My point is not that lawyers lie or cheat, my point is that Rebecca lies and cheats, and it turns out to be a sometimes lauded skillset as a lawyer, but it makes her not always a great friend or girlfriend. Or party planner. And Rebecca flips from job to guy when one isn't working for her. And back again.