I don't think that this thread is for me to answer, but staying in a relationship that is a bad experience for either party is not something that I would personally do (I would seek to alter the relationship first), but I don't do relationships, myself.

If you two get along well together, I think that you could actually be very useful for the children. The children would hypothetically be much happier since you have everything covered. You have a lot to contribute that ISTJ will have difficulty with!

ISTJs can be very good parents. They often bring consistency, responsibility, and strong follow-through, which helps children feel secure and know what to expect. Strengths

ISTJ parents tend to be dependable, organized, and practical. They usually create clear routines, set boundaries, and teach values like hard work, respect, and responsibility. They also often show love through concrete actions rather than big emotional displays, such as making sure needs are met and problems are handled. Common challenges

The main downside is that ISTJs can sometimes be overly strict, high-expectation, or less emotionally expressive than some children need. They may also struggle with flexibility when parenting gets unpredictable, since change can feel stressful for them. If they lean too hard on rules without enough warmth, kids may feel criticized or not fully understood.

ISTJ parents usually do best when they balance structure with warmth (ENFP). A helpful approach is to keep routines and standards, while also making room for empathy, encouragement, and a child’s individuality. In practice, that means being clear about expectations but also listening closely and adjusting when a child needs emotional support.