If my mom died and left a Trust leaving my brother and I each half of its worth, what do I do to get my money out?

The provisions of the trust govern as to how the trustee makes the distributions of assets. Suggest you consult an attorney with the expertise of administration of trusts to assist you.

You should read the trust instrument, it will tell you how the distributions to the beneficiaries are to be made, and whether or not a beneficiary can demand payments out of the trust.  I strongly suggest you consult an attorney, especially if you feel that the trustee is not being honest with you.