Is it abuse when your parents lock you out of the house when they're not home&its cold-you have no way to use the br-&you have autism&heart problems?

MAYBE: Depends on more factors and need more information. Do you live with your parents? Did you do something so they do not trust you? Did you lose your keys so they will not allow you to have them? Do you drive or have other relatives or friends? Do you work? You are no longer a minor child so you may need to explore other options. Try to speak with your parents and work out a plan.

Seek adult services: You may qualify for SSI & medicaid. Call your local social security administration office. Your state's office of disability (vocational rehabilitation) can help you find work. Describe your situation & ask what social & financial supports are available for you to live as independently as possible. Unless your parents became your legal guardian when you turned 18, you must do this for yourself.

Poor judgement: the parents used pooor judgement in locking yoiu out of the house. Parents will have to give a good reason for their action. In most jurisdictions, this behavior should be reported to the appropriate government authorities.