First, you can install low cost security cameras that will allow you to watch your home. These cameras will snap photos or video based on movement. You can find inexpensive choices on amazon. You can also look into inexpensive devices to secure your home. Some of them have alarms that will call you, or at least will make a lot of noise and scare someone off. With a camera such as this you can obtain the proof you need that someone has broken into your home, and hopefully you can identify who the person was. http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Daps&field-keywords=security%20camera&sprefix=secur%2Caps&rh=i%3Aaps%2Ck%3Asecurity%20camera
Second, if you haven't done so, change your locks now. If your boyfriend had a key, he can keep getting in. If you live in a rental, ask your landlord to change the locks. You will have to pay, but it will be worth it.
If you can, change your phone number so your boyfriend cannot call you any more. If you believe your phone has been hacked, wipe it, meaning put it back to factory settings and see if that helps resolve the problem. Make sure you change all of your passwords.
Gather as much evidence you can, so next time you go to the police you have proof.
Also, look into help from domestic violence groups in your area. They might be able to provide resources to help you.
I am very sorry you are going through this.
I am licensed in Pennsylvania. Members of my firm are licensed in various states, including Pennsylvania, New Jersey and New York. We handle cases involving personal injury (car accidents slip and falls, etc.,) medical malpractice, nursing home abuse, workers' compensation and social security disability. This post is not legal advice, but instead contains general educational information. Please do not act or refrain from acting based upon what you read in this post. Also please remember that this post does not form an attorney/client relationship between you and me. If you have specific legal questions, you should contact an attorney in your state for assistance.
Get the alarm, see if an attorney will send a legal letter to the ex (most attorneys will need at least a good faith information and belief basis that this is indeed the culprit). For a lawsuit you need proof, it does not appear you have that. You can keep reporting to the cops, but you can not force them to take action.
We do not have an attorney-client relationship. I am not your lawyer. The statements I have made do not constitute legal advice. Any statements I have made are based upon the very limited facts you have presented, and under the premise that you will consult with a local attorney. This is not an attempt to solicit business. This disclaimer is in addition to any disclaimers that this website has made. I am only licensed in California.