It sounds like you're going through a big life change, and it's totally understandable to feel a bit lonely. The good news is that Perth has a lot to offer, and there are plenty of people looking to connect!
Given your interests, you could try joining some social groups that focus on brunches, coffee meetups, dog walking clubs, or even beach clean-up initiatives. There are also online communities for people in Perth.
Putting yourself out there can be tough, but it's worth it to find your "person." You might be surprised at how many others are in a similar boat!