"Miss you. I love you."

I've just got to say something about this (more of a ramble than anything) - I've had these sorts of messages before and they're just annoying breadcrumbs/bait/whatever other descriptor you can think of. There's nothing of substance to them, they're just worthless drips of your ex's mixed feelings because she missed you a bit or feels guilty a bit. They're absolutely devastating to receive and will knock you on your ass, no question, but I'd strongly encourage you not to overthink them. More often than not they're just wishy-washy bullshit from a cheater who's facing consequences.

I've been in the position where I've anguished over those little texts only to discover later on that my ex was already setting up with the person they cheated with. A lot of cheaters just initiate contact like this when they have a fleeting moment of loneliness or boredom or they're just drunk. It's hardly ever the start of substantial growth or remorse in my experience, and personally, they now strike me as rather manipulative.