I too was given this advice from a HV, and I have to say that it worked for me, but it was not a pleasant experience. The situation was, my dd1 was 4 mths old, and I was returning to work full time, as a teacher. I felt I had to stop bfeeding, expressing milk at school just did not seem like an option. She would not take any kind of milk in any kind of receptacle with any kind of teat. I went up to stay with my parents, feeling that I wanted my mum's support. We spoke to two friends who had also been down this route, and their advice was the same, to just be persistent, and, if possible, to get someone else to do it, as they would be less emotionally attached. Mum felt confident she could handle it, so off we went. It was bloody awful - 24 hours later, dd was still not accepting a bottle, the screaming was horrendous, I was in pieces, and my dad decamped to the pub. We went to the local health clinic to seek advice, as I was worried about dehydration. A very nice HV suggested spooning in water to prevent dehydration, but otherwise to carry on. DD took the bottle a few hours later, and we never looked back from there. As I said, I cannot pretend it was easy, and I cried like I have never cried before, it seemed so cruel to dd. I feel emotional even now, typing this, and it was nearly 3 years ago. I also feel emotional thinking about how patient and brave my mum was, I could not have trusted anyone else to do this for me.
I am not a health professional, my advice is just based on my own experience - if, like me, there is not another option, time is tight, and you are pretty desperate, then try it. Could your mum or mil help out? or could your husband handle it?
From the bottom of my heart, I wish you success. Hope to hear how you got on.