Are we nearing the end

So ive been with my current partner for nearly 2 years. I have 3 children with the youngest 2 being his. We got together in rather forced way but none the less i loved him. We met at college while i was in a relationship with my eldest childs father. It was a very abusive relationship from him to me and i found comfort in my current partner and we became quite close. We slept together twice. With him in the full knowledge i was falling in love with him. After nasty exchanges after feeling used by him we stopped talking. We then got back in contact after i had split with my ex. An although he was seeing someone we grew close again. Him and his then gf went on a break and we ended up sleeping together and resulting in our first child being concieved. After the first month of brief exchanges we decided to try and make it work as a relationship. I had my suspitions that he was messing around with his ex and another girl but thought i was being paranoid. Anyway i went on to have our son by em c section and we grew closer than ever for two weeks until i used his laptop and went to go on fb it loaded his as he hasnt logged out there was all the messages between him and his ex. Over the next few weeks i found more and more and up until our son was born he had been seeing her. I confronted him and tried to throw him out but he wouldnt leave and it was 2 days before xmas and we made it work for the kids. We settled down and the trust started to come back and then after being on the pill and antobiotics i feel pg with our now 2 month old daughter. Things since then have gor worse again. I still cant get our of my head what he did to me when i was preg with our son, hes become lazy or if he does help he makes a big song and dance how fantastic he is even though i do it day in day out with 3 kids and and without a break where as his job involves him sitting at a pc all hours. Not exactly taxing. The thought of an intimate relationship with him makes me feel dirty and cheap and i just dont enjoy it anymore. I cant stand to be around him half the time and i cant help but find faults in the way he parents. My only friend i have confided in has told me she thinks it post natal depression but ive felt like it for a long time and dont feel its that as i when he is at work im a happy caring mum who spends lots of time with the kids in a calm home. He comes home and im stressed as he is also very clingy and is wanting cuddles and kisses when i juat cant physically do it anymore with him. Sorry for a long winded rant and i hope someone can make sense of it all and give me advice on what to

He sounds crap. Its a crappy situation. You deserve better. Theres no easy answer to this. If you leave, you have no money unless you go to work and raise kids all on your own. If you stay, you have the security, but can't stand being around him. I'd say your best option is to try and work it out with him. Say your still upset about what happened, and set your terms (e.g. him doing more housework / cooking) and make him work to show he appreciates you. I'm not married, and I don't have kids, so excuse me if this sounds a little cut and dry. Life is never EVER black and white or as simple as a 3 step solution. I hope you find a solution that suits you and your children (and possible your partner if you both want the relationship to work out).