I have done some reading up round this, having recently taken slightly early retirement following prostate cancer but wanting to work out how to maximise the situation for my wife retiring significantly early so we can enjoy some adventures. She is younger than me but has also had health issues that mean our window for being highly active in retirement may be shorter than for couples in optimal health (but of course we don't actually know ...)
We got financial advice, on a fee basis as recommended above. Once you have decided what to do you can operate it yourself without percentage-based fees which quickly amount to much more. His recommended investments were statistically unlikely to do so much better than my self-chosen index-tracker equivalents that they would have covered those extra costs.
Obviously your situation is unique to you, which is why no one can advise without all the information, but other people's experience might help you think about ideas. In our case my wife will have some bits of final salary pension from various past jobs but they would be seriously reduced by taking them early. Eventually though, when she finally reaches 67 and gets the state pension, those plus my pension will keep us reasonably comfortable. The question is how to get there from here.
My wife's current pension scheme is "defined contribution" which is what I assume yours is, producing a "pot" with her name on it within the company fund. Because she, like you, is over 55 she can take it as soon as she retires though for some reason not from the company scheme - she will need to transfer to a different external pension fund. The good news is that there are lots of options including several you can manage yourself for minimal fees (see the Monevator website for comparison calculations for what are called SIPPs). The deal with pension funds is that you can have 25% as a lump sum without tax, but anything after that is treated as income and subject to income tax. Our plan is that she will take the allowed lump sum and then draw down the remainder at the most you can without paying tax, i.e. just the threshold amount each year. It will leave us a little short, but we reckon we will be fine supplementing income from the upfront 25% plus the lump sum bit of my pension which is now in a building society.
There is a whole separate question of how to invest money held in a SIPP which you are planning to draw down relatively quickly. Money held as cash will get poor interest rates and lose out with inflation, but any unit trust type investment needs to be kept for at least 5 years or the short term fluctuations outweigh the potential gains (I have plumped for the relatively low risk stock-bond mix of the Vanguard LifeStrategy unit trust range). You can't take it out of the pension to put in a building society without paying tax upfront, which is what pension schemes avoid.