Abused by your father, and in essence, betrayed by your mother. What huge traumas from which to try to heal and deal. In Jewish bioethics we have a concept called l'faneynu, the answers depend on the exact situation of the person "who is before us." Someone abused as a child is not in the same precise halachic or ethical position with regard to the mitzvah of kibud av v'em, as one who was well-cared for in childhood.
An article in Olam Magainze (Summer 2001) by Rabbi Joseph Telushkin points out there is no commandment to love your parents. Yes, we are guided to: "Love your neighbor as yourself" (Lev. 19:18), 'And you shall love the Lord your God' (Deut. 6:5), And 'You shall love the stranger (Lev. 19:34). But not parents, they are only later analogized to God within Jewish tradition. Not a holy metaphor for your situation, it seems to me. Rabbi Telushkin explains Torah perhaps takes into consideration that love isn't something that's really possible to command in a human parent-child relationship, it may be present, absent or arise and then sometimes ebb and wane. And then, most pertinent to your question, he parenthetically notes: "In instances of parents who have physically or sexually abused their children, I believe that children do not owe the parents respect or anything else for that matter…” I wish to offer a slightly different take away from his important reasoning, in fact several different ways to possibly full the mitzvah of kibud av v'em without damaging yourself emotionally or spiritually. Ways of possible integrity.
In contemplating your situation it comes to me that there is a shared root meaning to the term kibbud, it is kaveid, "weight", to give weight to the existence or memory of a parent. That, perhaps you can do in fulfillment of this commandment. How? Maimonides, Talmudic sages and numerous other Jewish sources discuss situations such as yours and conclude a) you are not to subject yourself to further abuse and b) you might best see to your parents' physical needs from a second-hand distance. Yes, they conceived you and gave you life, so for this reason our tradition teaches a child isn't to completely abandon parents, sch as when they need to be cared for in illness, poverty or old age.
In several places in the Talmud including Kidushin 31b-32a the term honor is given a minimum set of criteria: “Honoring”: one must give him food and drink, one must dress him and cover/shelter him, and one must escort him in and out." Maimonides, as I understand him, allows for doing this by hiring someone with your parents' money first off, if this is what is needed to properly care for yourself. Today a child can hire an elder care attorney to also organize Medicare and/or Medicaid eligibility for parents, if that is something they can't do so themselves. Then, your own funds can be drawn upon, if you have sufficient to share, should other options fail.
And remember, save for in the privacy of therapeutic time with your closest friend or family members, a therapist or clergy person, maintaining careful ethics within your own personal life, which includes the mitzvah of refraining from maligning them to others outside of that small circle -- this will bring honor kavod to yourself, your family, teachers, many others and if you will, as the tradition would say, God.
But what about your role as a child in saying Kaddish when abusive parents die? Rising in their memory is intended to bring honor to their names. Is there a healthy way for you to do this? A book that I co-edited was just released this week titled
Mitzvah Stories: Seeds for Inspiration and Learning and within it is a story called "Honor" by Phil Cohen. In this story the inner thoughts of the main character are depicted during the season of his saying Kaddish for a father who was never emotionally accessible. By giving kavod, "weight" to his honest memories of his father, to the losses he mourns of needs never fulfilled in that relationship, by giving weight to what was withheld or impossible to give, he finds much more comes of the process of saying Kaddish than he might have anticipated. Reading the full story might be helpful to you and others.
Finally, an important way to give kavod to parents, is to donate to a charity in their names. You might do so, in this case, to charities that care for and work toward the prevention of child abuse, or research and treatment entities that seek to treat those who sexually abuse others. Judaism teaches the mitzvah of lo tikom, take no revenge, rather we have the option to do better than parents sometimes do, we can come up with create ways to partially address trauma by transforming this world through adding to the good.
May your path be blessed.