You got domestiqued by a emotional parasite as kitten, and now you got a adult cat missing territory...
It will be
hell.To keep it fertile, you necessarily need a enclosed garden no alternative. May be small a 40-50m2 if it is complex, full of plant and shit to hide.
If you sterilise it, heat will be less intense. You will not need enclosure, she will be rape but not be pregnant and will lean to hide heat to reduce rape rate.
But you need a garden. Or a gigantic balcony. Or a roof access. Or a unroofed place access. Inside cats are no exception absolutely idiot and degenerated.
