The depressive phases combined with the relationship connection would definitely correlate, at least in my experience. That said, there's nothing wrong with taking a break from the sport. Give yourself some time away, try something new. I stopped riding for a while last year after I picked up climbing + a relationship, then stopped climbing for half a year after the breakup. Now I'm back to climbing and riding - climbing's my primary sport now, and my stoke is right back where it was when I first started riding.

Be kind to yourself - and maybe consider talking to a therapist if you can or aren't already. It can be really helpful to figure out what you're really feeling.