My Mother died 5 years ago after a long illness that drained both me and my father of a certain amount of emotional strength. 3 years ago my 75-year old father took up with a 61-year-old, penniless woman he met at his yacht-club bar (after going thru 3 - that I know of - similar women at same bar), and has since began & developed a twisted, sexually-based, emotionally sadomasochistic relationship with her that has this past month spiraled into the depths. It would be almost funny if it wasn't so serious. I have cried myself to sleep almost every night since then from my remote motel room (I work on the road). My dying mother promised me (an only child) a good deal of inheritance that they both worked to build as an estate -- we are/were all hard-working engineer-types. Over the 3 years I have stood by (in and around my various stints on the road) and watched this conniving woman take mortar and brick out of this promise, one by one. I kept my mouth shut and even endured her zingers to my face about my career and roadie lifestyle (behind his back, naturally) for these 3 years -- I watched the new expensive car, the endless expensive meals out (I do not exaggerate, often with her friends and family included on his tab), the European vacation, the apartment of her own because she couldn't afford the rent (actually, her roommate also probably didn't like the drinking/sex nights), and now the inevitable -- the she couldn't afford the rent anymore on her place and moved in with him. She now complains her back hurts from her nursery-school job ( = her health is poor from excessive eating & drinking) and I know quitting her job and spending both his & Mom's SS (then marriage) is next.
As the beneficiary of the trust you are certainly entitled to a copy of the trust. I would suggest taking that copy to an attorney to assist you in interpreting the trust. If the trustee will not provide you with the copy, the attorney will be able to demand it for you.
The bottom line is that the trustee must follow the instructions in the trust. If they won't, the can be removed via litigation. Also, the person controlling the trust works for the trustee, not for the beneficiary. You will have to go to court to force your father to honor the trust.
The judge could even remove your father as trustee due to his health. Of course, taking your father to court is a sure-fire guarantee that you'll ruin your relationship with him, so this should be an act of last resort, but it would stop him using the trust part set aside for him on "stray" women.
I wish you luck.
As a fellow engineer I know you are or should be making more than $70k a year, you are 53, so you must be experienced. I assume you are Civil, I am EE, working in tech sales instead. Focus on your career, your earning potential is way above what you are spending your energy on. Let go, let dad have his girl, even if you do not care for her. Focus on your relationship with your husband, focus on your career. I have no idea what your rights, to this trust are, if you must pursue that do so at the expense of what is left of your relationship with your father....all for less than a year's engineering salary.
Allow yourself to let go of this, it is eating away at you....move on. Be happy.