Indoor becoming an outdoor?

[Mississippilessly]

We got our lovely car from a rescue 2 years ago. She had been a stray. Due to a mild cough they requested that she was rehomed as an indoor cat. We first lived in a flat and she was fine. However last year we moved to a house and she is getting more and more interested in outside. It's becoming harder to keep her in and a bit of a pain. I feel so guilty keeping her in. However, she does still have the cough. We also live on a main road and the house backs on to a railway line.
DH is against her going outside because of the safety aspect. Any thoughts please? I feel bad as we work long hours but I will be on maternity leave soon and will be off for 14 months. I can't see a harness working and due to the number of trees in the garden I can't cat proof it.
Thoughts?

[Allergictoironing]

If the back garden allows it, maybe look into building a Catio? They can get a bit of outdoor time at least that way, while being contained safely.

[ocelot41]

If it backs onto a railway line, I think your DH is right. Can you cat proof the garden?

[viccat]

As there's three reasons for keeping her in (main road, railway line, health issues) a catio that is around your back door seems the safest option, and then strictly never allow her out at the front of the house.

[Toddlerteaplease]

My parents adopted and indoor cat. He'd lived in a flat, very quickly after getting him it became clear that he wanted out. So they had to let him as he got aggressive. (He's very soppy otherwise)

[Mississippilessly]

Thanks for the replies. DH won't entertain a catio. I've tried.