A friend didn’t pay me back

Long story short I lended a friend $40 because she texted me saying her card is locked and she’d pay me back the following day (she was on vacation out the country) cool I cash app her. I honestly didn’t have the money but wanted to help cause I could imagine what that’s like, so I asked my husband. That was last Thursday…it’s now Tuesday. When I message her casually she just says “ima send it gotta go to the bank” or “ ima send it tomorrow had to get a new card” I need the money myself I’m 28 weeks pregnant… me personally I’ve borrowed money before from other people but I ALWAYS pay them back. It’s just the principle of it she’s not even messaging me to say “hey I haven’t forgot i just don’t have it right now” etc. she acts as if she doesn’t owe me and it pisses me off this always happens to me with people i try to help. We’re not even the best of friends she a former coworker hung out 3 times and keep in touch every now and then. Should I message her

“Keep the $40 just make sure you never need me for nothing else” cause that’s really lame. My husband says to just let it go