Ex just sent me a pic of us... Means anything?

So I broke with my ex almost 4 weeks ago. Well she dumped me actually. At first she restricted me on FB and it was like 4 days no contact at all, didn't pick up the phone either. Then after some messages I sent her she told me she wanted to be alone, space and all that crap. Well now I got her on FB again and sometimes message/chat briefly.
The thing is yesterday she talked to me again on FB, a bit longer tha usual. She also mentioned "why did you become a fan of that?" (A liquor delivery site) "I'm the facebook cop remember? haha" Something I used to tease her with. She also nugged me about drinking booze cause she's all fit and stuff.
I answered " I don't know whose cop you are but certainly not mine, thankfully, I just click like on stuff to check it out later".
Next thing I know out of the blues she sent me a pic of us together during a trip we made to my email.
What do you think of this? I sent her a message saying "Why do you send me that pic to my email? I've already seen it..." No reply so far just sent that and I know shes online and has read it.
Do you think it is a good sign? Or maybe she's clearing pics from her camera and wanted me to have it? By the way we appear cheerful and happy on the pic and she said before she liked it. Maybe I shouldn't have said anything about it...but what do you think?
And for those lads whose advice is "just move on"... I'm on it, but if I got back with her it would be on my terms and give me confidence to check elsewhere for other prospects and maybe dump her as she did to me. Don't give me the "that's unethical" thing. Bches are unethical all the time. Also having someone to fk wouldnt be that bad.
So what do you think about the pic...I guess iI should not take her so seriously but might it be a sign that she misses me or something?

Also another question, IF and only if she wants to hang out again or come back with me should I accept right away? Maybe if I do that she will take me for granted and not respect me. But if I play it too difficult she might move on.
I haven't seen her since we broke up and wanted to freeze her until past new years. Do you think I should cut off every sort of communication including posting, commenting, messaging, chatting and/or liking stuff in her profile?
Should I send another message depending of her reply or no reply before freezing for good?
Any insights are welcome thanks for reading the long post.

Yes it's a sure sign she's interested, or was thinking of you and memories at the time

And yes when she wants to meet be a little difficult about it. Don't respond to her immediately on any messages, make her work for it. Tease her a bit, good ol Cat String Theory

And for the record getting back with an Ex even just to fool around is foolish, but it's a mistake I've made (and regretted) a few times so I know you're gonna need to learn that for yourself, no big deal

But I have to address your ethics piece. Girls will f with you If you let them, but if you want to be a PUA there is a certain code
What that means is that if it comes up you be honest with her that you're in date mode, seeing other people, and confused about your feelings for her (assuming you guys get to the point of fooling around). Do it on your terms tho and don't accept her rules or parameters. Have fun and break her heart by all means but not using lies or deceipt. The less available to her you are the harder she will want you back, if you are a PUA you can use all of this to understand what motivates girls and how to maintain control of your direction the whole time

Finally don't cut off all communication, just make it sporadic. If she messages you respond back a day later or something. If you don't respond to her interest she will stop, but if you respond appropriately and make her curious she will work much harder

Thanks man, I'll do that. You've been most helpful. I get that abouthe the "code" you mention. I am not deceptive or the like unless they are to me, and generally not even then.
Thanks for the advice let's see what happens, I'm not in a rush and I have lerned from past mistakes (fortunately). I know what you mean about getting back with ex's, I don't normally do it either (depending of the circumstances)..
Any other comments welcome.

By the way....after some minutes she replied saying "what photo...I don't remember sending any pic, at least consciously".
I told her about it (I think she of course knew what I was talking about) and then she said...well I don't know and changed the topic. Did'nt ask her again about that. Now im getting unplugged from her till after new years at least.