I know exactly what you mean - it would be nice to be sometimes groped over the kitchen sink or something - it is hard work having to keep trying to instigate sex...
Most men are not turned off if their partners gain a little weight - for many it makes things better, though they still tend to prefer traditional figures to look at...
Many women would envy your friendly and companiable marriage without sexual demands - but as you desire sex something must be done!
Caroline is right, there are many possible variables that could be affecting or causing the situation - testosterone patches is one of the common hospital prescriptions according to a hospital secretary I know and I urge you to use all your womanly wiles to persuade him to get tested.
It could be he has a naturally low libido or it could be he is one of the few men who are turned off by an over-weight figure or he could be one of the few a-sexual men...
If he is forever on the computer looking at porn and masturbating it is probable that ordinary people and ordinary sex is no longer good enough for him...
You do have a right to a sex life and plain language is best. Try telling your hubby to buy you a vibrator and some other toys and in future it is going to be his Saturday night duty to use them on you until you are well-and-truly satisfied even if he doesn't want any himself - not many men can resist the sight and sound of a woman enjoying herself and he might get the urge to join in!
Time to stop being so much of a lady!
There is another possibility to consider if all else fails. If he has been like that since the beginning is it possible he is not turned-on by women? There are a huge number of marriages that have been conducted by men who are bisexual but their preference is sex with other men. Celibacy would be an acceptable alternative to infidelity for a lot of the more honourable types...
If a dog doesn't get fed at home it will get food from somewhere else - the ultimate threat or solution - either a clandestine affair or an open threat to your husband that you will be open to offers from other men - that might get his juices flowing!
That sort of thing might rock the boat too much - you might be better off masturbating yourself and making the best of a bad job, especially if you can persuade hubby to cuddle you at the same time...