For once I agree with ****.....and Ranger combined.
Call and leave a message if she doesnt answer. If she answers tell her this. If she doesnt answer, leave the message and ALSO send the exact same thing in a text so you have documented proof:
"Hey its Ryan. I am going to swing by tomorrow around 5pm. I need to get my stuff back, including the tickets. Leave them in a box on your porch and when I pick it up I will put your stuff in there as well. If its not there I will contact the police. Thanks and have a nice day".
Thats it. If its not on her porch when you tell her youre swinging by, call the cops. Ask them to kindly give her a call to persuade her to give you the shyte back.
If not, you can probably find her and her new man in the exact section, row and seat numbers as your tickets were for the concert.
Wait on the police threat... Hear me out...
In order for her to be held accountable legally, you are going to need to have her admit she knowingly has the tickets in her possession.
If you threaten her with calling the police, she will respobd that she doesn't know where your tickets are. If you then file a police report, she will shred the tickets.
I suggest you ask for your stuff back and give her a time and place that you will pick up your stuff, as suggested earlier. Then mention "as you know, I left the tickets to x concert at your house. I plan on attending the concert, which is on DATE at TIME, so I would like to get the tickets back and find someone to go with. Is leaving my stuff in the porch at X time on Y day going to work for you? I will leave your stuff as well"
At this point it might be worth it to go a little bett and add "unless you still want to go with me?"
Remember, the goal is to get her to ADMIT she HAS the tickets. You already have proof that you purchased them.
Get her to admit that she has your stuff and/or the tickets and, if she refuses to play ball, call the cops and let them surprise her with a visit.
If she doesn't respond to the text, call the cops and discuss your options with them, and follow thru on what you can.
Sucky people piss me off...