Hi Hanginin, I am so sorry for your situation. I am in much the same position. My husband too started having a relationship possibly non-sexual, when I started my cancer treatment. I too, am far from young. We have built up a lot together. We have a social network, 2 homes, social position, family and friends together which would be jeopardised by formal divorce. I have not divorced but decided to stay in the marriage for my own benefit and for selfish reasons too, not out of low self esteem. I will stay to enjoy the fruits of the life I helped build. Why should I suffer a lowering of my lifesstyle because he is a cheat?
My self esteem did plunge when I realised that his serial emotional affairs were humiliating for me. One of his obsessions was with a girl half his age. Staying in the relationship because it suits me, may be seen as using him, but he is not being straight with me. I am staying out of choice because it suits me at present, I feel more in control. Further it gives me time to adjust and I would be more able to face a break-up if I have had time to prepare both emotionally and financially.
I had some telephone counselling with Relate. The counsellor did say that he thought our relationship was not viable because my husband if so dishonest, I think He further went on to say that my husband is probably a very unhappy man, that he is having extreme difficulty coming to terms with aging. This helped diminish the anger I feel. I did tell my husband that he had "changed the rules of our relationship" which clearly worried him. However I do think that by continually surveying the field of single women, he might find someone else and leave. By then I will have built up my own new life. I am staying in our overseas holiday home. He visits weekends. He does not want to lose me at the moment. I think he has seen friends with young wives and young children. He would not want to have young children around him, or to be paying for children long into his old age. I do think obsessions with younger women reflect sadness and disappointment in himself. He is aging and feeling "is this all there is". Younger women represent nostalgia for his lost youth. My husband had something of a wake up call when colleagues started openly mocking him for his flirting. He does not want to look like an old fool/dirty old man whom people laugh about. Where does this leave you. I do not think your husband is without feelings for you. However he does not much care that he is hurting you, he is putting his own needs before yours.
He is possibly seeking novelty, lost youth, excitement, which new relationships,obsessions appear to offer. The problem is in his head.
I have started to build a new life. Like you I could replace him, and that thought alone sustains me. I need not be alone if I so choose. Only you are responsible for your own happiness. Don't give him the power of deciding whether or not you will be happy. As a spin-off the happier you appear, the more appealing you appear, and the more worthy of his respect. Hide your neediness, it will diminish more quickly that way. Of course you don't want to throw 27 years away.
If you want his attention, hide your neediness, be mysterious. Be "out" when he calls. Get new exciting hobbies, meet new people that he doesn't know. Make him realise he could lose you. He may come round, you may then find you really don't want him so much, or he may not, in which case you have at least got a full and happy life. I wouldn't do anything to end the marriage, too soon. But do protect yourself financially. If he meets someone, he could start secreting funds away. He could fold his business to prevent you getting an order for maintenance. Make sure both homes are in joint names and be aware that some men will forge the wife's signature in order to realise funds/sell properties. He is abroad, it is very easy for him. You need to protect yourself financially. If there is any hint that he wants a divorce, get your petition in in the UK as wives get a better deal in the Uk than anywhere else. Don't let him file for divorce overseas, beat him to it if it comes to that.
Sorry if this is long and rambling. I do so understand your dilemma. It so hurts.