Money Diary: An Arts Administrator & Single Mum In Glasgow On 16k

Welcome to Money Diaries, where we're tackling what might be the last taboo facing modern working women: money. We're asking a cross-section of women how they spend their hard-earned money during a seven-day period – and we're tracking every last penny.
This week: "I’m a 34-year-old arts administrator living and working in Glasgow. I am also a single mum to an 8-year-old daughter (G) and a 4-year-old son (B). I separated from their dad two and a half years ago and our relationship now consists of co-parenting via WhatsApp (definitely not how I saw things panning out when we got together at the tender age of 19). I’ve since bought him out of the flat we owned together, he’s moved in with his girlfriend and they have the kids one or two nights a week, depending on his shift patterns.
The separation completely wiped out my savings. After a few months of financial woe, I realised I was entitled to tax credits (my claim predated universal credit, which would entitle me to less), which have been an absolute lifeline. I’m no longer in my overdraft at the end of each month and I’ve slowly been able to start rebuilding my savings. I’m constantly aware that if I were to lose my job there would be no-one else to pay the bills so I save as much as I can and tend to be pretty thrifty with my earnings. I keep a fierce eye on my direct debits, cancelling anything that’s not being used and switching my utilities to the best deals as often as I can. This has saved me over £200 a month over the past few years. I use this saving as justification for the occasional homeware splurge (my main weakness)."
Occupation: Part-time administrator (currently WFH)
Industry: Arts
Age: 34
Location: Glasgow
Salary: £16k (25 hours per week)
Paycheque amount: £1,185 after tax, NI and pension.
Additional income: Child/working tax credits £114, child benefit £35, child maintenance £20 x2
Number of housemates: Two: my 8-year-old daughter (G) and 4-year-old son (B). As housemates go, they're pretty ace!
Monthly Expenses
Housing costs: £300 mortgage on a two-bedroom tenement flat, £140 council tax, factor fees (including building insurance) £85.
Loan payments: £0
Savings? ISA £1,800, Loyalty Saver £2,200, Help to Save Scheme £900, kids' ISAs £3,500 each. I’ve always been an avid saver (being the daughter of a financial advisor will do that to a girl) but my savings were wiped out six years ago when we bought our flat and again two years ago when I had to buy my ex out of the mortgage (two of my grandparents passed away at the same time as us separating so I was able to put £15k inheritance towards buying him out. I'm eternally thankful to my late grandparents for essentially enabling me to keep hold of the family home, though I do often wonder how we could have used that money had we not separated). 
Utilities: £6 gas/electric (this should be £55 but I sweet-talked multiple friends and family into switching to Bulb with my referral code so currently enjoying the benefit of all the £50 credits), £22 broadband, £6 SIM only with Giffgaff.
Other: £3.99 Audible (usually £7.99 but I 'cancel' every few months to get the offer), £10 donation to Refuweegee (a Glasgow-based charity supporting refugees), £5.79 life insurance, £10 contents insurance (the irony that the contents of my flat are apparently worth more than my life is not lost on me). Standing orders into savings: ISA £100, Help to Save £50, kids ISAs £100 each (from child maintenance/child benefit). This locks away £350 pcm. If I have anything left at the end of the month I move this into an easy access savings account for future holidays/flat improvements – the monthly amount can vary between £0-250.
Monthly expenses currently paused due to lockdown: £45 monthly bus pass, £9.99 Spotify, 2 x £25 kids swimming lessons, 1 x £20 kids gymnastics.