If you want a government that doesn't align itself with either Israel or Palestine then this Conservative government is absolutely not for you. 80% of Conservative MPs belong to the Friends of Israel group - as I've said before, there is no Conservative Friends of Palestine group.
At least the Labour and the Lib Dem parties contain groups for both Friends of Israel and Friends of Palestine.
There are some stupid and unpleasant people in all parties. If there are holocaust deniers in any of those parties they are a very small minority who most people have not time for. In my 68 years, I have never in my personal experience, heard anybody denying that the holocaust happened. Neither, in my personal experience, have I heard anyone being racist about Jewish people - other than seeing footage on TV of football supporters singing inane and offensive songs, which target both Muslim and Jewish people. That is not to say that I have never heard anyone strongly criticise Israel's actions - I have done so myself. Why should I not? I'm extremely critical of the rulers of Saudi Arabia and the government of Pakistan but that doesn't make me Islamophobic.
As for terrorists, it is not just "terrorist groups" who terrorise. States can terrorise too - as was seen in Chile and South Africa. Yet these nations were supported by some western governments, including our own. But when the terrorising is done by our supposed "friends", every effort is made to maintain a low profile. It was only when ordinary people - then often described as "rabble rousers", "communists", etc. etc. - came together to campaign and protest (often being arrested for acts of "civil disobedience") and the tyranny of these governments became more widely understood, that governments had to change their tune. Thatcher and other Conservative MPs described Pinochet as a "friend" and Mandela as a "terrorist" but why were those that terrorised him and all non-white people not described in the same way?
As for Israel, the UN High Commission Inquiry recently reported, re the recent Gaza demonstration:
" More than 6,000 unarmed demonstrators were shot by military snipers, week after week at the protest sites by the separation fence. ..
... “There can be no justification for killing and injuring journalists, medics, and persons who pose no imminent threat of death or serious injury to those around them. Particularly alarming is the targeting of children and persons with disabilities,”
....“Many young persons’ lives have been altered forever. 122 people have had a limb amputated since 30 March last year. Twenty of these amputees are children.”
.."The Commission took note of the Israeli claim that the protests by the separation fence masked “terror activities” by Palestinian armed groups. The Commission found however that the demonstrations were civilian in nature, with clearly stated political aims."
