Relationship RP in general seems to attract those types, with or without ERP. That's why, after learning the hard way, I only RP romances with people I know and trust. It's just easier to talk things out and ensure everyone's on the same page if you already feel comfortable speaking to them as a player. Of course there can still be problems but it does lower the odds quite a bit in my experience. Honest communication is the key, as has been said, so if problems do arise you can tackle them before they escalate into something worse.