MabelMay, I have been through all of this too! I'm a SAHM of ds, 2 yrs 4 mths, and dd, 7 mths. I gave up work completely when ds was born but I do struggle with being a SAHM at times.
My top tips are: plan your week as if it was a working week (which it is, kind of). Put in the practical stuff like trips to the supermarket but also schedule in some fun stuff which you can actually enjoy with the kids, and that should include lots of adult company for you. There is a reason so many "pushy mums" go to a different class every day, and I don't think it's for the children, I think it's so they will be able to talk to other adults and not go mad!
If you don't do the planning, there is a risk that every day will just drift by in a sea of boring domestic jobs, daytime TV and frustration with your children.
I have been very lucky and have 2 regular groups who meet for tea every Monday and Wednesday and that's been a life saver for me. Do you know anyone you could ask to meet up with, or are there any ready-made groups in your area which you could join? Also think about toddler playgroups as they are a good meeting ground for other mums.
Lastly, be aware that you are going through one of the worst bits. It does get better! Very young children are pretty limited in terms of interaction, let alone conversation, but my ds at nearly 2 and a half is so much more fun now than he was a year ago.